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A171251
Sums of two (not necessarily distinct) Mersenne primes (A000668)
5
6, 10, 14, 34, 38, 62, 130, 134, 158, 254, 8194, 8198, 8222, 8318, 16382, 131074, 131078, 131102, 131198, 139262, 262142, 524290, 524294, 524318, 524414, 532478, 655358, 1048574, 2147483650, 2147483654, 2147483678, 2147483774, 2147491838
OFFSET
1,1
COMMENTS
All terms are even, since all terms of A000668 are odd. This motivates to introduce A171252 = (1/2) * A171251, see there for further information.
FORMULA
A171251(n) = 2*A171252(n) = A000668(i) + A000668(j) where n = i*(i-1)/2+j.
MATHEMATICA
With[{mps=Select[2^Range[50]-1, PrimeQ]}, Union[Total/@Tuples[mps, 2]]] (* Harvey P. Dale, Aug 11 2012 *)
PROG
(PARI) concat(vector(#A000668, i, vector(i, j, A000668[i]+A000668[j]))) /* having defined A000668 as vector with initial terms of A000668 */
CROSSREFS
Sequence in context: A129119 A259020 A259021 * A074980 A363172 A059218
KEYWORD
nonn
AUTHOR
M. F. Hasler, Mar 06 2010
STATUS
approved