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%I A109216 #9 Mar 21 2013 13:25:20
%S A109216 3,17,3,3,593,3,3,32993,3,3,2097593,3,3,73,3,3,8589935681,3,3,17,3,3,
%T A109216 11,3,3,83,3,3,11,3,3,17,3,3,857,3,3,71329,3,3,59,3,3,19,3,3,11,3,3,
%U A109216 17,3,3,4561633,3,3,2940725100673,3,3,193,3,3,1867,3,3,17,3,3,44449,3,3,19,3,3
%N A109216 Smallest factor of 2^(2n+1)+(2n+1)^2.
%C A109216 For n={0, 1, 4, 7, 10, 16, 1003, 1063, 1879, 14677, 17326, 28642, 49534} we have the only primes of the form 2^(2n+1)+(2n+1)^2: A064539. Cases 2n+1 == 1, 2 (mod 3) are trivial and may be omitted.
%H A109216 Vincenzo Librandi, <a href="/A109216/b109216.txt">Table of n, a(n) for n = 0..100</a>
%t A109216 Table[ With[ {k=2}, FactorInteger[ n^k + k^n]] [[1, 1]], {n, 1, 145, 2}]
%Y A109216 Cf. A064539, A109215.
%K A109216 base,nonn
%O A109216 0,1
%A A109216 _Zak Seidov_, Jun 24 2005
%E A109216 More terms from _Robert G. Wilson v_, Jun 24 2005

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