A087745 Numbers A001317 repeated.

1, 1, 3, 3, 5, 5, 15, 15, 17, 17, 51, 51, 85, 85, 255, 255, 257, 257, 771, 771, 1285, 1285, 3855, 3855, 4369, 4369, 13107, 13107, 21845, 21845, 65535, 65535, 65537, 65537, 196611, 196611, 327685, 327685, 983055, 983055, 1114129, 1114129

Offset

0,3

Comments

Triangles A049444, A049459, A051338, A051379, A051523 (Mitrinovic's triangles) mod 2 converted to decimal.

Sequence [1, 3, 5, 15, 17, 51, 85, 255, 257, ...] = A001317.

Links

Table of n, a(n) for n=0..41.

Prog

(Python)
def A087745(n): return sum((bool(~(m:=n>>1)&m-k)^1)<<k for k in range((n>>1)+1)) # Chai Wah Wu, May 02 2023

Crossrefs

Cf. A001317, A049444, A049459, A051338, A051378, A051523.

Sequence in context: A147048 A110192 A014414 * A087756 A243305 A334075

Adjacent sequences: A087742 A087743 A087744 * A087746 A087747 A087748

Keyword

easy,nonn

Author

Philippe Deléham, Oct 02 2003

Extensions

Definition corrected and edited by Omar E. Pol, Dec 24 2008

Status

approved