A164740 (2^p-(p+2))/p as p runs through the primes.

0, 1, 5, 17, 185, 629, 7709, 27593, 364721, 18512789, 69273665, 3714566309, 53634713549, 204560302841, 2994414645857, 169947155749829, 9770521225481753, 37800705069076949, 2202596307308603177

Offset

1,3

Links

Table of n, a(n) for n=1..19.

Formula

a(n) = 2*A007663(n)-1. [T. D. Noe, Aug 24 2009]

Mathematica

f[n_] := Block[{p = Prime@n}, (2^p - p - 2)/p]; Array[f, 15]
Table[(2^p-p-2)/p, {p, Prime[Range[20]]}] (* Harvey P. Dale, Aug 15 2017 *)

Crossrefs

Sequence in context: A090886 A097490 A355277 * A053678 A090645 A206328

Adjacent sequences: A164737 A164738 A164739 * A164741 A164742 A164743

Keyword

nonn

Author

Tanin (Mirza Sabbir Hossain Beg) (mirzasabbirhossainbeg(AT)yahoo.com), Aug 24 2009

Extensions

Edited by N. J. A. Sloane, Aug 24 2009

Extended and offset changed by T. D. Noe and Robert G. Wilson v, Aug 24 2009

Status

approved