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A340912
Central terms of triangle A340910.
1
1, 1, 6, 63, 907, 16208, 340458, 8169034, 220494839, 6638599425, 221835477385, 8197807088637, 333879685074774, 14929308189076011, 729701504761143784, 38801435534565069687, 2233844275229192069586, 138592433800490757379259
OFFSET
0,3
PROG
(PARI) {A340910(n, k) = my(A=1); for(i=1, n, A = sum(m=0, n, x^m/(1 - x*y*A^m +x*O(x^n))) ); polcoeff(polcoeff(A, n, x), k, y)}
for(n=0, 20, print1(A340910(2*n, n), ", "))
(PARI) {A340910(n, k) = my(A=1); for(i=1, n, A = sum(m=0, n, x^m*y^m/(1 - x*A^m +x*O(x^n))) ); polcoeff(polcoeff(A, n, x), k, y)}
for(n=0, 20, print1(A340910(2*n, n), ", "))
CROSSREFS
Sequence in context: A229451 A132078 A113669 * A121415 A227278 A295267
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jan 28 2021
STATUS
approved