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A294250
Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of e.g.f.: exp(Product_{j=1..n} (1+x^j) - 1).
6
1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 3, 1, 0, 1, 1, 3, 13, 1, 0, 1, 1, 3, 19, 49, 1, 0, 1, 1, 3, 19, 97, 261, 1, 0, 1, 1, 3, 19, 121, 681, 1531, 1, 0, 1, 1, 3, 19, 121, 921, 5971, 9073, 1, 0, 1, 1, 3, 19, 121, 1041, 8491, 50443, 63393, 1, 0, 1, 1, 3, 19, 121, 1041
OFFSET
0,13
LINKS
FORMULA
B(j,k) is the coefficient of Product_{i=1..k} (1+x^i).
A(0,k) = 1 and A(n,k) = (n-1)! * Sum_{j=1..min(A000217(k),n)} j*B(j,k)*A(n-j,k)/(n-j)! for n > 0.
EXAMPLE
Square array A(n,k) begins:
1, 1, 1, 1, 1, ...
0, 1, 1, 1, 1, ...
0, 1, 3, 3, 3, ...
0, 1, 13, 19, 19, ...
0, 1, 49, 97, 121, ...
0, 1, 261, 681, 921, ...
CROSSREFS
Columns k=0..5 give A000007, A000012, A118589, A294251, A294252, A294253.
Rows n=0 gives A000012.
Main diagonal gives A293840.
Sequence in context: A062719 A305161 A250484 * A117417 A231345 A271344
KEYWORD
nonn,tabl
AUTHOR
Seiichi Manyama, Oct 26 2017
STATUS
approved