A307505 Number T(n,k) of partitions of n into distinct parts whose bitwise XOR equals k; triangle T(n,k), n>=0, 0<=k<=n, read by rows.
1, 0, 1, 0, 0, 1, 0, 0, 0, 2, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 2, 1, 0, 0, 0, 1, 0, 2, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 1, 0, 4, 0, 1, 0, 1, 0, 0, 0, 4, 0, 1, 0, 2, 1, 0, 1, 0, 5, 0, 0, 0, 1, 0, 2, 0, 0, 0, 4, 0, 2, 0, 1, 0, 0, 0, 5, 1, 0, 5, 0, 0, 0, 2, 0, 1, 0, 4, 0, 2
Offset: 0
Examples
Triangle T(n,k) begins: 1; 0, 1; 0, 0, 1; 0, 0, 0, 2; 0, 0, 1, 0, 1; 0, 1, 0, 0, 0, 2; 1, 0, 0, 0, 1, 0, 2; 0, 0, 0, 0, 0, 0, 0, 5; 0, 0, 0, 0, 1, 0, 4, 0, 1; 0, 1, 0, 0, 0, 4, 0, 1, 0, 2; 1, 0, 1, 0, 5, 0, 0, 0, 1, 0, 2; ...
Links
- Alois P. Heinz, Rows n = 0..360, flattened
- Wikipedia, Bitwise operation
- Wikipedia, Partition (number theory)
Crossrefs
Programs
-
Maple
b:= proc(n, i, k) option remember; `if`(n=0, x^k, `if`(i<1, 0, b(n, i-1, k)+b(n-i, min(n-i, i-1), Bits[Xor](i, k)))) end: T:= n-> (p-> seq(coeff(p, x, i), i=0..n))(b(n$2, 0)): seq(T(n), n=0..14);
Formula
T(n,k) = 0 if n+k is odd.