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A338755 Central coefficients of number triangle A210590. 2
1, 5, 119, 5205, 324569, 26519745, 2681170547, 323104570789, 45224035123553, 7211322045457101, 1290620989042420815, 256193650031596282005, 55863607060241676345961, 13273922770286234753307065, 3413846723448521483558054235, 944832714523233697801280445525, 280003865538498845896076940256065 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..100

FORMULA

a(n) = A210590(2*n, n) = (-1)^n * A234937(2*n, n).

PROG

(PARI) {a(n) = my(t='t); (2*n)!*polcoef(polcoef(prod(k=1, 2*n, (1-x^k+x*O(x^(2*n)))^(-1-t)), 2*n), n)}

(PARI) {a(n) = my(t='t); if(n==0, 1, (2*n)!*polcoef(polcoef(exp(sum(k=1, 2*n, (1+t)*sigma(k)*(x^k+x*O(x^(2*n)))/k)), 2*n), n))}

CROSSREFS

Cf. A210590, A234937.

Sequence in context: A156962 A065818 A139189 * A155202 A168599 A193328

Adjacent sequences:  A338752 A338753 A338754 * A338756 A338757 A338758

KEYWORD

nonn

AUTHOR

Seiichi Manyama, Nov 07 2020

STATUS

approved

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Last modified May 8 19:28 EDT 2021. Contains 343666 sequences. (Running on oeis4.)