A318122 a(0) = a(1) = 1; a(n) = Sum_{k=0..n-2} gcd(a(k), a(n-k-2)).

1, 1, 1, 2, 3, 4, 5, 6, 8, 8, 13, 10, 16, 18, 21, 20, 28, 20, 30, 50, 36, 26, 67, 58, 48, 46, 72, 64, 76, 56, 93, 72, 96, 96, 138, 126, 112, 102, 160, 114, 160, 150, 144, 126, 128, 118, 273, 190, 252, 130, 230, 180, 260, 248, 312, 212, 208, 320, 422, 460, 296, 452, 493, 260, 436, 280

Offset

0,4

Links

Table of n, a(n) for n=0..65.

N. J. A. Sloane, Transforms

Mathematica

a[0] = a[1] = 1; a[n_] := a[n] = Sum[GCD[a[k], a[n - k - 2]], {k, 0, n - 2}]; Table[a[n], {n, 0, 65}]

Crossrefs

Cf. A007464, A007477, A318123.

Sequence in context: A351988 A214964 A097502 * A265568 A265552 A303936

Adjacent sequences: A318119 A318120 A318121 * A318123 A318124 A318125

Keyword

nonn

Author

Ilya Gutkovskiy, Aug 18 2018

Status

approved