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A318620
a(0) = a(1) = 1; for n > 1, a(n) = Sum_{k=0..n-2} a(k) AND a(n-k-2).
1
1, 1, 1, 2, 3, 2, 3, 2, 6, 6, 9, 8, 14, 14, 17, 12, 14, 14, 22, 20, 16, 12, 35, 52, 50, 54, 62, 76, 76, 84, 107, 80, 78, 86, 118, 116, 124, 60, 114, 176, 216, 168, 166, 160, 224, 276, 265, 288, 262, 374, 412, 424, 336, 344, 394, 392, 468, 464, 622, 740, 892, 960, 1121
OFFSET
0,4
LINKS
N. J. A. Sloane, Transforms
Eric Weisstein's World of Mathematics, AND
MAPLE
a:= proc(n) option remember; `if`(n<2, 1,
add(Bits[And](a(k), a(n-k-2)), k=0..n-2))
end:
seq(a(n), n=0..80); # Alois P. Heinz, Aug 30 2018
MATHEMATICA
a[0] = a[1] = 1; a[n_] := a[n] = Sum[BitAnd[a[k], a[n - k - 2]], {k, 0, n - 2}]; Table[a[n], {n, 0, 62}]
CROSSREFS
Cf. A007461.
Sequence in context: A015886 A255354 A344349 * A287748 A260233 A108656
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Aug 30 2018
STATUS
approved