A077753 a(0) = 2, a(1) = 1, a(2n) = a(2n-1) * a(2n-2), a(2n+1) = a(2n-1) + a(2n).

2, 1, 2, 3, 6, 9, 54, 63, 3402, 3465, 11787930, 11791395, 138996138862350, 138996150653745, 19319928257600060753067000750, 19319928257600199749217654495, 373259627878816004843210480238884928715510929499405871250

Offset

0,1

Links

Table of n, a(n) for n=0..16.

Maple

a:= proc(n) option remember; `if`(n<2, 2-n,
     `if`(n::odd, a(n-1)+a(n-2), a(n-1)*a(n-2)))
    end:
seq(a(n), n=0..16);  # Alois P. Heinz, Dec 22 2025

Crossrefs

Cf. A039941, A248479.

Sequence in context: A277631 A277633 A001037 * A122086 A385388 A082594

Adjacent sequences: A077750 A077751 A077752 * A077754 A077755 A077756

Keyword

nonn,easy

Author

Amarnath Murthy, Nov 20 2002

Extensions

More terms from Sascha Kurz, Jan 04 2003

Edited by N. J. A. Sloane, May 21 2008 at the suggestion of R. J. Mathar

Offset corrected from 0 to 1 by Antti Karttunen, Oct 26 2014

a(0)=2 prepended by Alois P. Heinz, Dec 22 2025

Status

approved