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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).

%I A318620 #11 Feb 16 2025 08:33:56
%S A318620 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,
%T A318620 76,76,84,107,80,78,86,118,116,124,60,114,176,216,168,166,160,224,276,
%U A318620 265,288,262,374,412,424,336,344,394,392,468,464,622,740,892,960,1121
%N A318620 a(0) = a(1) = 1; for n > 1, a(n) = Sum_{k=0..n-2} a(k) AND a(n-k-2).
%H A318620 Alois P. Heinz, <a href="/A318620/b318620.txt">Table of n, a(n) for n = 0..10000</a>
%H A318620 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%H A318620 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/AND.html">AND</a>
%p A318620 a:= proc(n) option remember; `if`(n<2, 1,
%p A318620       add(Bits[And](a(k), a(n-k-2)), k=0..n-2))
%p A318620     end:
%p A318620 seq(a(n), n=0..80); # _Alois P. Heinz_, Aug 30 2018
%t A318620 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}]
%Y A318620 Cf. A007461.
%K A318620 nonn
%O A318620 0,4
%A A318620 _Ilya Gutkovskiy_, Aug 30 2018