A081291 Complement of A072795.

0, 3, 6, 7, 8, 14, 15, 16, 17, 18, 19, 20, 21, 22, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128

Offset

0,2

Comments

This gives positions of those terms in A063171 which begin with digits 11... Also the elements of table A072764 which do not occur in the leftmost column. See the comment at A081292.

Links

Table of n, a(n) for n=0..63.

Formula

a(0)=0, a(n) = n + A014137(A081288(n)-1).

a(n) = A080300(A081292(n)) = A081289(n) + n - A081290(n).

Prog

(PARI) A014137(n) = sum(k=0, n, binomial(2*k, k)/(k+1); );
A081288(n) = my(i=0); while(binomial(2*i, i)/(i+1) <= n, i++); i;
a(n) = if (n==0, 0,  n + A014137(A081288(n)-1)); \\ Michel Marcus, Apr 28 2020

Crossrefs

Cf. A072795, A014137, A081288.

Cf. A080300, A081289, A081290, A081292.

Sequence in context: A189098 A241007 A139451 * A189095 A188968 A189211

Adjacent sequences: A081288 A081289 A081290 * A081292 A081293 A081294

Keyword

nonn

Author

Antti Karttunen, Mar 17 2003

Status

approved