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A221207
Primes of the form 2^(n-2)*(n+2)^2 + 1.
0
2, 17, 2593, 5308417, 26214401, 57802753, 584652423169, 5566277615617, 24807731101697, 2128654511374337, 114923510727115685920505857, 626707144888223764167681638401, 28901765777295687591430290881352276511750619137
OFFSET
1,1
EXAMPLE
a(0) = 2 = 2^(0-2)*(0+2)^2 + 1 = (1/4) * 4 + 1.
MATHEMATICA
Select[Table[2^(n - 2)*(n + 2)^2 + 1, {n, 0, 200}], PrimeQ] (* T. D. Noe, Apr 05 2013 *)
PROG
(PARI) for(n=0, 1e3, is(ispseudoprime(t=2^(n-2)*(n + 2)^2+1), print1(t", "))) \\ Charles R Greathouse IV, Mar 18 2014
CROSSREFS
Sequence in context: A284706 A092415 A274053 * A274015 A279884 A060353
KEYWORD
nonn,less
AUTHOR
Irina Gerasimova, Feb 21 2013
STATUS
approved