A048721 Binary packing of Fibonacci sequence A000045.

0, 1, 3, 7, 23, 151, 4247, 1052823, 8590987415, 18014407100469399, 309485009839359475825250455, 11150372599265311880252868975683656578240663, 6901746346790563787434755873427398051716420852423255530846180802039959

Offset: 0

Author

Antti Karttunen, Mar 30 1999

Keywords

• nonn

Comments

Prime values of a(n) begin 3, 7, 23, 151, i.e., for n = 2, 3, 4, 5. Semiprime values of a(n) begin 4247 = 31 * 137, 1052823 = 3 * 350941, i.e., for n = 6, 7. - Jonathan Vos Post, May 09 2005

Crossrefs

Cf. A000045, A005203, A048722, A036571.

Formula

a(0) = 0, a(n) = a(n-1)+(2^(Fib(n+1)-1)).