A071885 Trajectory of 38 under map x -> A002487(x)*A002487(x+1).

38, 70, 117, 198, 368, 210, 558, 1312, 693, 3920, 2438, 6900, 17138, 43792, 105939, 553150, 862695, 5466578, 262720694, 8088309190, 155799611901, 2918284055518, 415202250061643, 1166813484199476, 224311803609338424, 81023210443114539600, 8227824387593035424874

Offset

0,1

Links

Alois P. Heinz, Table of n, a(n) for n = 0..56

Maple

b:= proc(n) option remember; `if`(n<2, n,
     (q-> b(q)+(n-2*q)*b(n-q))(iquo(n, 2)))
    end:
a:= proc(n) option remember; `if`(n=0, 38,
     (t-> b(t)*b(t+1))(a(n-1)))
    end:
seq(a(n), n=0..26);  # Alois P. Heinz, Apr 27 2026

Crossrefs

Cf. A002487, A071884, A071886, A071887.

Sequence in context: A321997 A343974 A335483 * A032506 A044104 A044485

Adjacent sequences: A071882 A071883 A071884 * A071886 A071887 A071888

Keyword

nonn

Author

N. J. A. Sloane and J. H. Conway, Jun 10 2002

Status

approved