A386558 Square array A(n,k), n >= 0, k >= 0, read by antidiagonals: A(n,k) = binomial((k+1)*n+k-1,n)/(n+1).
1, 1, 0, 1, 1, 0, 1, 2, 2, 0, 1, 3, 7, 5, 0, 1, 4, 15, 30, 14, 0, 1, 5, 26, 91, 143, 42, 0, 1, 6, 40, 204, 612, 728, 132, 0, 1, 7, 57, 385, 1771, 4389, 3876, 429, 0, 1, 8, 77, 650, 4095, 16380, 32890, 21318, 1430, 0, 1, 9, 100, 1015, 8184, 46376, 158224, 254475, 120175, 4862, 0
Offset: 0
Examples
Square array begins: 1, 1, 1, 1, 1, 1, 1, ... 0, 1, 2, 3, 4, 5, 6, ... 0, 2, 7, 15, 26, 40, 57, ... 0, 5, 30, 91, 204, 385, 650, ... 0, 14, 143, 612, 1771, 4095, 8184, ... 0, 42, 728, 4389, 16380, 46376, 109668, ... 0, 132, 3876, 32890, 158224, 548340, 1533939, ...
Links
- Wikipedia, Fuss-Catalan number
Crossrefs
Programs
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PARI
a(n, k) = binomial((k+1)*n+k-1, n)/(n+1);
Formula
For k > 0, A(n,k) = r * binomial(n*p+r,n)/(n*p+r), the Fuss-Catalan number with p=k+1 and r=k.
G.f. of column k: (1/x) Series_Reverion( x*(1-x)^k ).