A376768 a(1) = 2; thereafter, a(n) = c*A376767(n-1) + 1, where c=4 if n is odd, c=2 if n is even.

2, 5, 11, 221, 24311, 1182000821, 698562969831336611, 975980445639153806859347417915257421, 476268915135000629546288739757931900755190480621127468115605921390156911

Offset

1,1

Comments

This is the sequence of dampening coefficients for the divergent series 1 + 2 + 1 + 2 + 1 + 2 + ...

Links

Table of n, a(n) for n=1..9.

N. J. A. Sloane, A Nasty Surprise in a Sequence and Other OEIS Stories, Experimental Mathematics Seminar, Rutgers University, Oct 10 2024, Youtube video; Slides

Crossrefs

Cf. A374663, A376767.

Sequence in context: A123165 A098438 A225955 * A236073 A064772 A107989

Adjacent sequences: A376765 A376766 A376767 * A376769 A376770 A376771

Keyword

nonn

Author

N. J. A. Sloane, Nov 03 2024

Status

approved