A272646 a(0)=a(1)=1; thereafter a(n) = (4*n-3)*a(n-1) + 2*a(n-2).

1, 1, 7, 65, 859, 14733, 311111, 7807241, 227032211, 7507677445, 278238129887, 11422778680257, 514581516871339, 25237339884056125, 1338608176888717303, 76351140762424998521, 4660096802861702344387, 303058994467535502382197, 20920390811865673069060367, 1527794647255129205046171185

Offset

0,3

Links

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

D. H. Lehmer, Arithmetical periodicities of Bessel functions, Annals of Mathematics, 33 (1932): 143-150. The sequence is on page 148.

Maple

f:=proc(n) option remember; if n <= 1 then 1 else 2*f(n-2)+(4*n-3)*f(n-1); fi; end;
[seq(f(n), n=0..30)];

Mathematica

RecurrenceTable[{a[0]==a[1]==1, a[n]==(4n-3)a[n-1]+2a[n-2]}, a, {n, 20}] (* Harvey P. Dale, Apr 07 2019 *)

Crossrefs

Sequence in context: A069015 A097819 A152525 * A220067 A109779 A239984

Adjacent sequences: A272643 A272644 A272645 * A272647 A272648 A272649

Keyword

nonn

Author

N. J. A. Sloane, May 09 2016

Status

approved