A244588 a(n) = n OR 6.

6, 7, 6, 7, 6, 7, 6, 7, 14, 15, 14, 15, 14, 15, 14, 15, 22, 23, 22, 23, 22, 23, 22, 23, 30, 31, 30, 31, 30, 31, 30, 31, 38, 39, 38, 39, 38, 39, 38, 39, 46, 47, 46, 47, 46, 47, 46, 47, 54, 55, 54, 55, 54, 55, 54, 55, 62, 63, 62, 63, 62, 63, 62, 63, 70, 71, 70, 71

Offset: 0

Author

Gary Detlefs, Jun 30 2014

Keywords

• nonn
• easy

Comments

a(n) = n if n is congruent to (6, 7) mod 8.

Crossrefs

Cf. similar sequences listed in A244587.

Programs

Magma

[BitwiseOr(n, 6): n in [0..80]]; // Bruno Berselli, Jul 01 2014

Maple

with(Bits): seq(Or(n,6), n = 0..60);

Mathematica

Table[BitOr[n, 6], {n, 0, 80}] (* Bruno Berselli, Jul 01 2014 *)

Formula

a(n) = (n+6) - (n AND 6).

a(n) = (n XOR 6) + (n AND 6).

a(n) = n + ( 6*floor((n+2)/2) mod 8 ).

Sum_{n>=0} (-1)^n/a(n) = sqrt(2)*Pi/4 - sqrt(2)*log(sqrt(2)+1)/2 - log(2)/2. - Amiram Eldar, Aug 07 2023