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A164740
(2^p-(p+2))/p as p runs through the primes.
2
0, 1, 5, 17, 185, 629, 7709, 27593, 364721, 18512789, 69273665, 3714566309, 53634713549, 204560302841, 2994414645857, 169947155749829, 9770521225481753, 37800705069076949, 2202596307308603177
OFFSET
1,3
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: A097490 A355277 A309178 * A053678 A090645 A206328
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