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a(n) = least odd number which can be represented in the form p + 2*k^2, k>0, in n different ways.
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%I #2 Mar 30 2012 17:30:31

%S 1,5,13,21,49,55,91,139,259,181,301,391,481,559,619,829,859,1069,1111,

%T 1081,1489,1609,1741,1951,2029,2971,2341,3379,3769,3331,3589,3961,

%U 4525,4189,5281,4801,4975,6361,7579,5911,6439,7111,6319,9931,11059,8869

%N a(n) = least odd number which can be represented in the form p + 2*k^2, k>0, in n different ways.

%t a = Table[ 0, {100} ]; Do[ c = 0; k = 1; While[ n - 2*k^2 > 1, If[ PrimeQ[ n - 2*k^2 ], c++ ]; k++ ]; If[ a[ [ c ] ] == 0, a[ [ c ] ] = n ], { n, 1, 70801, 2 } ]

%K nonn

%O 0,2

%A _Robert G. Wilson v_, Mar 14 2001