A003177 a(n) = ceiling(24(2^n-1)/n).

24, 36, 56, 90, 149, 252, 436, 765, 1363, 2456, 4467, 8190, 15122, 28086, 52428, 98303, 185042, 349524, 662258, 1258290, 2396744, 4575604, 8753330, 16777215, 32212254, 61946643, 119304647, 230087533

Offset

1,1

Links

Table of n, a(n) for n=1..28.

R. J. Penrose, Puzzle, Twistor Newsletter, No. 10 (July 1980), p. 22.

R. J. Penrose, Puzzle, Twistor Newsletter, No. 10 (July 1980), p. 22. [Cached copy]

R. J. Penrose, Solution to puzzle, Twistor Newsletter, No. 41, p. 37, 1996.

R. J. Penrose, Solution to puzzle, Twistor Newsletter, No. 41, p. 37, 1996. [Cached copy]

Crossrefs

Cf. A003176, A003138, A121056.

Sequence in context: A143645 A003176 A003138 * A038530 A262428 A281925

Adjacent sequences: A003174 A003175 A003176 * A003178 A003179 A003180

Keyword

nonn

Author

N. J. A. Sloane

Status

approved