mvw

# n*k different objects in k bins of size n each
#
# http://math.stackexchange.com/q/1940138/86776

load "set.rb" 

def fac(n)
  if n == 0
    return 1
  end

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result = 2286878604508883/69984000000000 = 32.67716341605057

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D = 6

def f(i, j)
  i2 = i.clone
  i2[j] -= 1
  i2[j-1] += 1
  return i2
end

def e(i)

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found 1: (0, 0, 5), w = 8
found 2: (0, 1, 4), w = 0
found 3: (0, 2, 2), w = 4
found 4: (0, 3, 0), w = 8
found 5: (1, 0, 3), w = 10
found 6: (1, 1, 2), w = 2
found 7: (1, 2, 0), w = 6
found 8: (2, 0, 2), w = 0
found 9: (2, 1, 0), w = 4
found 10: (3, 0, 0), w = 2

mvw

# ordertypes.rb
# http://math.stackexchange.com/q/1657371/86776

NMAX=68

found = 0
(0..NMAX).each do |n1|
  w1 = 68 - n1 * 22
  (0..NMAX).each do |n2|
    w2 = w1 - n2 * 20

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N = 100

def brute_force
  puts "searching {#{-N}, #{N}}^2, checking #{(2*N+1)**2} pairs:"
  found = 0
  checked = 0
  (-N..N).each do |m|
    a = m*m
    ap = a + 1
    (-N..N).each do |n|

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N = 10000

def brutus
  m = N+N
  xm = N
  ym = N
  (1..N).each do |y|
    y_cube = y * y * y
    (1..N).each do |x|
      if 360 * x == y_cube

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test1:
  succeeded: 1002001
  failed: 0
  success rate: 100.0 %
test2:
  succeeded: 1000000
  failed: 0
  success rate: 100.0 %

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# digit_wise_average.rb

# the usual average of two numbers
def average(a, b)
  (a + b) / 2.0
end

# convert "n" into array of digits regarding "base"
# lowest power stored first
def to_a(n, base)

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searching ..
k = 1:
n digits:
[0:1, 1:0, 2:0, 3:0, 4:0, 5:0, 6:0, 7:0, 8:0, 9:0]
OK - congrats!

k = 2017:
n digits:
[0:198, 1:202, 2:202, 3:201, 4:202, 5:202, 6:201, 7:202, 8:202, 9:201]
OK - congrats!