A081769 a(n)-th term of the continued fraction for 2*Sum_{k>=0} 1/2^(2^k) is 2.

5, 13, 18, 23, 25, 30, 38, 43, 45, 53, 58, 60, 65, 70, 78, 83, 85, 93, 98, 103, 105, 110, 118, 120, 125, 133, 138, 140, 145, 150, 158, 163, 165, 173, 178, 183, 185, 190, 198, 203, 205, 213, 218, 220, 225, 230, 238, 240, 245, 253, 258, 263, 265, 270, 278, 280

Offset

1,1

Links

Table of n, a(n) for n=1..56.

Formula

a(n) = 5*n + 0 or + 3 and it appears that a(n) = 5*n+3*A073089(n+2).

Example

The continued fraction for 2*Sum_{k>=0} 1/2^(2^k) is 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, ... hence a(1)=5.

Crossrefs

Cf. A006466, A073089, A076214.

Sequence in context: A347475 A294136 A120062 * A188030 A101864 A190432

Adjacent sequences: A081766 A081767 A081768 * A081770 A081771 A081772

Keyword

easy,nonn

Author

Benoit Cloitre, Apr 09 2003

Extensions

Name corrected by Jason Yuen, Dec 26 2025

Status

approved