A276960 a(n) = A000262(n)^2.

1, 1, 9, 169, 5329, 251001, 16410601, 1416242689, 155514288609, 21128299481809, 3474052208270281, 679096541717605881, 155504946117339546289, 41199419449380747871369, 12496348897836314700506409

Offset

0,3

Links

Table of n, a(n) for n=0..14.

Formula

Recurrence: (2*n+3)*a(n+3)-(2*n+5)*(3*n^2+13*n+13)*a(n+2)+(n+2)*(n+1)*(2*n+3)*(3*n^2+13*n+13)*a(n+1)-n^2*(n+1)^3*(n+2)*(2 n+5)*a(n) = 0.

Asymptotic: a(n) ~ exp(-2*n+4*sqrt(n)-1)*n^(2*n-1/2)/2 * (1 - 5/(24*sqrt(n)) - 35/(1152*n)).

Mathematica

Table[HypergeometricPFQ[{-n+1, -n}, {}, 1]^2, {n, 0, 100}]

Prog

(Maxima) makelist(hypergeometric([-n+1, -n], [], 1)^2, n, 0, 12);

Crossrefs

Cf. A000262, A105278, A008297, A276964.

Sequence in context: A243949 A202836 A052774 * A122725 A012130 A151997

Adjacent sequences: A276957 A276958 A276959 * A276961 A276962 A276963

Keyword

nonn

Author

Emanuele Munarini, Sep 27 2016

Status

approved