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A362125
Square array T(n,k), n>=0, k>=0, read by antidiagonals downwards, where column k is the expansion of 1/(1 - x*(1+x)^k)^k.
1
1, 1, 0, 1, 1, 0, 1, 2, 2, 0, 1, 3, 7, 3, 0, 1, 4, 15, 18, 5, 0, 1, 5, 26, 55, 47, 8, 0, 1, 6, 40, 124, 198, 118, 13, 0, 1, 7, 57, 235, 571, 681, 290, 21, 0, 1, 8, 77, 398, 1320, 2500, 2263, 702, 34, 0, 1, 9, 100, 623, 2640, 7026, 10504, 7341, 1677, 55, 0
OFFSET
0,8
FORMULA
T(n,k) = Sum_{j=0..n} (-1)^j * binomial(-k,j) * binomial(k*j,n-j) = Sum_{j=0..n} binomial(j+k-1,j) * binomial(k*j,n-j).
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, ...
0, 1, 2, 3, 4, 5, ...
0, 2, 7, 15, 26, 40, ...
0, 3, 18, 55, 124, 235, ...
0, 5, 47, 198, 571, 1320, ...
0, 8, 118, 681, 2500, 7026, ...
PROG
(PARI) T(n, k) = sum(j=0, n, binomial(j+k-1, j)*binomial(k*j, n-j));
CROSSREFS
Columns k=0..2 give A000007, A000045(n+1), A362126.
Main diagonal gives A362080.
Sequence in context: A294498 A292860 A265609 * A261718 A144074 A261780
KEYWORD
nonn,tabl
AUTHOR
Seiichi Manyama, Apr 08 2023
STATUS
approved