Math symbols for the compose key

.XCompose

# Math

<Multi_key> <A> <A>                  : "∀"
<Multi_key> <E> <E>                  : "∃"
<Multi_key> <exclam> <E> <E>         : "∄"

<Multi_key> <minus> <0>              : "−"
<Multi_key> <KP_Subtract> <KP_0>     : "−"
<Multi_key> <asterisk> <1>           : "⋅"
<Multi_key> <KP_Multiply> <KP_1>     : "⋅"
<Multi_key> <x> <x>                  : "×"
<Multi_key> <asciicircum> <period>   : "·"
<Multi_key> <o> <equal>              : "∘"
<Multi_key> <period> <equal>         : "•"
<Multi_key> <exclam> <Right>         : "¬"

<Multi_key> <i> <n>                  : "∈"
<Multi_key> <exclam> <i> <n>         : "∉"
<Multi_key> <n> <i>                  : "∋"
<Multi_key> <exclam> <n> <i>         : "∌"
<Multi_key> <braceleft> <parenleft>  : "⊂"
<Multi_key> <braceleft> <parenright> : "⊃"
<Multi_key> <braceleft> <equal> <parenleft> : "⊆"
<Multi_key> <braceleft> <exclam> <equal> <parenleft>: "⊊"

<Multi_key> <braceleft> <u> : "∪"
<Multi_key> <braceleft> <n> : "∩"
<Multi_key> <braceleft> <U> : "⋃"
<Multi_key> <braceleft> <N> : "⋂"

<Multi_key> <T> <T>            :  "⟙"
<Multi_key> <T> <exclam>       :  "⟘"
<Multi_key> <backslash> <slash> : "∨"
<Multi_key> <slash> <backslash> : "∧"
<Multi_key> <n> <backslash> <slash> : "⋁"
<Multi_key> <n> <slash> <backslash> : "⋀"
<Multi_key> <backslash> <underscore> <slash>: "⊻"

<Multi_key> <s> <q>                  : "√"
<Multi_key> <3> <r> <t>              : "∛"
<Multi_key> <KP_3> <r> <t>           : "∛"
<Multi_key> <4> <r> <t>              : "∜"
<Multi_key> <KP_4> <r> <t>           : "∜"

<Multi_key> <parenleft> <plus>                 <parenright> : "⊕"
<Multi_key> <parenleft> <KP_Add>               <parenright> : "⊕"
<Multi_key> <parenleft> <minus>                <parenright> : "⊝"
<Multi_key> <parenleft> <KP_Subtract>          <parenright> : "⊖"
<Multi_key> <parenleft> <x> <x>                <parenright> : "⊗"
<Multi_key> <parenleft> <asterisk>             <parenright> : "⊛"
<Multi_key> <parenleft> <KP_Multiply>          <parenright> : "⊛"
<Multi_key> <parenleft> <asciicircum> <period> <parenright> : "⊙"
<Multi_key> <parenleft> <slash>                <parenright> : "⊘"
<Multi_key> <parenleft> <KP_Divide>            <parenright> : "⊘"
<Multi_key> <parenleft> <o> <equal>            <parenright> : "⊚"
<Multi_key> <parenleft> <equal>                <parenright> : "⊜"
<Multi_key> <parenleft> <minus> <minus>        <parenright> : "⊝"

<Multi_key> <Q> <E> <D>        :  "∎"


<Multi_key> <bar> <space>                        :  "∣"
<Multi_key> <bar> <slash>                        :  "∤"
<Multi_key> <bar> <bar> <space>                  :  "∥"
<Multi_key> <bar> <bar> <slash>                  :  "∦"
<Multi_key> <bar> <bar> <asciitilde>             :  "⫳"
<Multi_key> <underscore> <bar> <bar> <underscore>: "⟂"

<Multi_key> <Multi_key> <S> <u> <m>             : "∑"
<Multi_key> <Multi_key> <P> <r> <o> <d>         : "∏"
<Multi_key> <Multi_key> <C> <o> <p> <r> <o> <d> : "∐"
<Multi_key> <Multi_key> <I> <n> <t>             : "∫"
<Multi_key> <Multi_key> <2> <I> <n> <t>         : "∬"
<Multi_key> <Multi_key> <KP_2> <I> <n> <t>      : "∬"
<Multi_key> <Multi_key> <3> <I> <n> <t>         : "∭"
<Multi_key> <Multi_key> <KP_3> <I> <n> <t>      : "∭"
<Multi_key> <Multi_key> <o> <I> <n> <t>         : "∮"
<Multi_key> <Multi_key> <S> <I> <n> <t>         : "∯"
<Multi_key> <Multi_key> <V> <I> <n> <t>         : "∰"

<Multi_key> <asterisk> <S> <Up>   : "⎲"
<Multi_key> <asterisk> <S> <Down> : "⎳"
<Multi_key> <parenleft>    <Up>   : "⎛"
<Multi_key> <parenleft>    <Left> : "⎜"
<Multi_key> <parenleft>    <Down> : "⎝"
<Multi_key> <parenright>   <Up>   : "⎞"
<Multi_key> <parenright>   <Left> : "⎟"
<Multi_key> <parenright>   <Down> : "⎠"
<Multi_key> <bracketleft>  <Up>   : "⎡"
<Multi_key> <bracketleft>  <Left> : "⎢"
<Multi_key> <bracketleft>  <Down> : "⎣"
<Multi_key> <bracketright> <Up>   : "⎤"
<Multi_key> <bracketright> <Left> : "⎥"
<Multi_key> <bracketright> <Down> : "⎦"
<Multi_key> <braceleft>    <Up>   : "⎧"
<Multi_key> <braceleft>    <Left> : "⎨"
<Multi_key> <braceleft>    <Right>: "⎪"
<Multi_key> <braceleft>    <Down> : "⎩"
<Multi_key> <braceright>   <Up>   : "⎫"
<Multi_key> <braceright>   <Left> : "⎬"
<Multi_key> <braceright>   <Right>: "⎪"
<Multi_key> <braceright>   <Down> : "⎭"
<Multi_key> <parenleft> <less>     : "〈"
<Multi_key> <parenright> <greater> : "〉"

<Multi_key> <6> <6>         : "∂"
<Multi_key> <KP_6> <KP_6>   : "∂"
<Multi_key> <d> <e> <l>     : "∇"
<Multi_key> <d> <d> <e> <l> : "∆"

<Multi_key> <plus> <minus>                     : "±"
<Multi_key> <KP_Add> <KP_Subtract>             : "±"
<Multi_key> <asciitilde> <space>               : "∼"
<Multi_key> <exclam> <asciitilde>              : "≁"
<Multi_key> <asciitilde> <colon>               : "∻"
<Multi_key> <asciitilde> <Left>                : "∽"
<Multi_key> <asciitilde> <minus>               : "≃"
<Multi_key> <asciitilde> <KP_Subtract>         : "≃"
<Multi_key> <exclam> <asciitilde> <minus>      : "≄"
<Multi_key> <exclam> <asciitilde> <KP_Subtract>: "≄"
<Multi_key> <minus> <asciitilde>               : "≂"
<Multi_key> <KP_Subtract> <asciitilde>         : "≂"
<Multi_key> <asciitilde> <equal>               : "≅"
<Multi_key> <asciitilde> <exclam> <equal>      : "≆"
<Multi_key> <exclam> <asciitilde> <equal>      : "≇"
<Multi_key> <asciitilde> <asciitilde>          : "≈"
<Multi_key> <exclam> <asciitilde> <asciitilde> : "≉"
<Multi_key> <equal> <8>              : "∝"
<Multi_key> <equal> <KP_8>           : "∝"
<Multi_key> <equal> <d> <e> <f>      : "≝"
<Multi_key> <equal> <quest>          : "≟"
<Multi_key> <colon> <equal>          : "≔"
<Multi_key> <exclam> <equal>         : "≠"
<Multi_key> <less> <equal>           : "≤"
<Multi_key> <greater> <equal>        : "≥"
<Multi_key> <exclam> <less>          : "≮"
<Multi_key> <exclam> <greater>       : "≯"
<Multi_key> <0> <less> <less>          : "≪"
<Multi_key> <KP_0> <less> <less>       : "≪"
<Multi_key> <0> <greater> <greater>    : "≫"
<Multi_key> <KP_0> <greater> <greater> : "≫"

<Multi_key> <equal> <Right>                 : "⇒"
<Multi_key> <equal> <Left>                  : "⇐"
<Multi_key> <equal> <Left> <Right>          : "⇔"
<Multi_key> <equal> <exclam> <Right>        : "⇏"
<Multi_key> <equal> <exclam> <Left>         : "⇍"
<Multi_key> <equal> <exclam> <Left> <Right> : "⇎"

<Multi_key> <minus> <Up>    : "↑"
<Multi_key> <minus> <Right> : "→"
<Multi_key> <minus> <Down>  : "↓"
<Multi_key> <minus> <Left>  : "←"

<Multi_key> <8> <8>         : "∞"
<Multi_key> <KP_8> <KP_8>   : "∞"

<Multi_key> <l> <l> : "ℓ"


<Multi_key> <bar> <0>   : "𝟘"
<Multi_key> <bar> <KP_0>: "𝟘"
<Multi_key> <bar> <1>   : "𝟙"
<Multi_key> <bar> <KP_1>: "𝟙"
<Multi_key> <bar> <2>   : "𝟚"
<Multi_key> <bar> <KP_2>: "𝟚"
<Multi_key> <bar> <3>   : "𝟛"
<Multi_key> <bar> <KP_3>: "𝟛"
<Multi_key> <bar> <4>   : "𝟜"
<Multi_key> <bar> <KP_4>: "𝟜"
<Multi_key> <bar> <5>   : "𝟝"
<Multi_key> <bar> <KP_5>: "𝟝"
<Multi_key> <bar> <6>   : "𝟞"
<Multi_key> <bar> <KP_6>: "𝟞"
<Multi_key> <bar> <7>   : "𝟟"
<Multi_key> <bar> <KP_7>: "𝟟"
<Multi_key> <bar> <8>   : "𝟠"
<Multi_key> <bar> <KP_8>: "𝟠"
<Multi_key> <bar> <9>   : "𝟡"
<Multi_key> <bar> <KP_9>: "𝟡"
<Multi_key> <bar> <A>: "𝔸"
<Multi_key> <bar> <B>: "𝔹"
<Multi_key> <bar> <C>: "ℂ"
<Multi_key> <bar> <D>: "𝔻"
<Multi_key> <bar> <E>: "𝔼"
<Multi_key> <bar> <F>: "𝔽"
<Multi_key> <bar> <G>: "𝔾"
<Multi_key> <bar> <H>: "ℍ"
<Multi_key> <bar> <I>: "𝕀"
<Multi_key> <bar> <J>: "𝕁"
<Multi_key> <bar> <K>: "𝕂"
<Multi_key> <bar> <L>: "𝕃"
<Multi_key> <bar> <M>: "𝕄"
<Multi_key> <bar> <N>: "ℕ"
<Multi_key> <bar> <O>: "𝕆"
<Multi_key> <bar> <P>: "ℙ"
<Multi_key> <bar> <Q>: "ℚ"
<Multi_key> <bar> <R>: "ℝ"
<Multi_key> <bar> <S>: "𝕊"
<Multi_key> <bar> <T>: "𝕋"
<Multi_key> <bar> <U>: "𝕌"
<Multi_key> <bar> <V>: "𝕍"
<Multi_key> <bar> <W>: "𝕎"
<Multi_key> <bar> <X>: "𝕏"
<Multi_key> <bar> <Y>: "𝕐"
<Multi_key> <bar> <Z>: "ℤ"
<Multi_key> <bar> <asterisk> <g>: "ℽ"
<Multi_key> <bar> <asterisk> <p>: "ℼ"
<Multi_key> <bar> <asterisk> <G>: "ℾ"
<Multi_key> <bar> <asterisk> <P>: "ℿ"
<Multi_key> <bar> <asterisk> <S>: "⅀"
<Multi_key> <bar> <KP_Multiply> <g>: "ℽ"
<Multi_key> <bar> <KP_Multiply> <p>: "ℼ"
<Multi_key> <bar> <KP_Multiply> <G>: "ℾ"
<Multi_key> <bar> <KP_Multiply> <P>: "ℿ"
<Multi_key> <bar> <KP_Multiply> <S>: "⅀"

<Multi_key> <t> <r> <i>    : "△"
<Multi_key> <d> <e> <l>    : "∇"
<Multi_key> <a> <l> <e> <f>: "ℵ"

<Multi_key> <&> <Right>    : "⃗" # combining vector arrow

To use this do I need to store this file in my home directory?

To use this do I need to store this file in my home directory?

I stored this in my home directory, then logged out and logged in back. Things working as expected.

Thanks!

For <Multi_key> <parenleft> <less> and <Multi_key> <parenleft> <greater> you can use the ⟨ and ⟩ symbols respectively.