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A165991 Numbers n such that 3+2^n is not prime. 0
0, 5, 8, 9, 10, 11, 13, 14, 17, 19, 20, 21, 22, 23, 24, 25, 26, 27, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 85, 86, 87 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Complement of A057732.

EXAMPLE

For n=0, 3+2^0=4 is not prime. n=5, 3+2^5=35=5*7, not prime. n=8, 3+2^8=259=7*37 not prime.

CROSSREFS

Sequence in context: A021633 A178309 A205862 * A191977 A101079 A066812

Adjacent sequences:  A165988 A165989 A165990 * A165992 A165993 A165994

KEYWORD

nonn

AUTHOR

Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Oct 03 2009

EXTENSIONS

Entries checked - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 05 2009

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Last modified February 15 11:03 EST 2012. Contains 205763 sequences.