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a(0) = a(1) = 1; for n > 1, a(n) = Sum_{k=0..n-2} a(k) OR a(n-k-2).
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%I #7 Aug 31 2018 03:47:37

%S 1,1,1,2,3,8,13,30,52,112,217,446,864,1750,3469,6976,13892,27828,

%T 55550,111158,222224,444458,888747,1777546,3554844,7109666,14218740,

%U 28437336,56874024,113747200,227493165,454985872,909968764,1819934952,3639866058,7279725522,14559441844

%N a(0) = a(1) = 1; for n > 1, a(n) = Sum_{k=0..n-2} a(k) OR a(n-k-2).

%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/OR.html">OR</a>

%F a(n) ~ c * 2^n, where c = 0.2118674483116007242958168442155...

%p a:= proc(n) option remember; `if`(n<2, 1,

%p add(Bits[Or](a(k), a(n-k-2)), k=0..n-2))

%p end:

%p seq(a(n), n=0..40); # _Alois P. Heinz_, Aug 30 2018

%t a[0] = a[1] = 1; a[n_] := a[n] = Sum[BitOr[a[k], a[n - k - 2]], {k, 0, n - 2}]; Table[a[n], {n, 0, 36}]

%Y Cf. A007460.

%K nonn

%O 0,4

%A _Ilya Gutkovskiy_, Aug 30 2018