main.dart

// The total number of cards in the cube.
const C = 540;

// The number of piles to create.
const p = 8;

void main() {
  var indices = [
    for (var i = 0; i < p; i++) ...List.filled((C / p).floor(), i + 1),
    // Randomly assign the last C % p numbers to piles without
    // assining any to duplicate piles.
    ...(List.generate(p, (i) => i + 1)..shuffle()).take(C % p)
  ]..shuffle();

  print(indices.join(" "));
}