A259905 n*a(n+1) = (2*n^2+2n-1)*a(n)+(n+1)*a(n-1); a(0)=1, a(1)=2.

1, 2, 8, 47, 371, 3676, 43822, 610493, 9730757, 174624086, 3483890996, 76489299307, 1832590219063, 47577493251632, 1330483562569946, 39870448222541561, 1274615495706568457, 43299625736778117418, 1557589082593773410272, 59147557572252556858151

Offset

0,2

Links

Table of n, a(n) for n=0..19.

Formula

a(n) ~ (BesselI(0,1) + BesselI(1,1)) * 2^(n-1) * n!. - Vaclav Kotesovec, Jul 09 2015

Mathematica

RecurrenceTable[{a[0]==1, a[1]==2, (n)*a[n+1]== (2n^2 +2*n-1)*a[n] + (n+1)*a[n-1]}, a, {n, 30}]

Crossrefs

Sequence in context: A317366 A009566 A349588 * A329096 A233337 A199136

Adjacent sequences: A259902 A259903 A259904 * A259906 A259907 A259908

Keyword

nonn,easy

Author

G. C. Greubel, Jul 07 2015

Status

approved