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%I #11 Jul 13 2015 12:20:59
%S 10,26,122,362,842,3482,3722,5042,6242,10202,17162,19322,32762,39602,
%T 73442,121802,143642,167282,201602,212522,271442,323762,326042,398162,
%U 410882,436922,546122,564002,674042,776162,863042,982082,1062962,1079522,1104602,1142762,1190282,1274642,1324802,1371242
%N Numbers that are both 1 + square of a prime and twice a prime.
%H Giovanni Resta, <a href="/A259979/b259979.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[2*10^6],PrimeQ[Sqrt[#-1]]&&PrimeQ[#/2]&] (* _Ivan N. Ianakiev_, Jul 13 2015 *)
%t Select[Prime@ Range[10^4], PrimeQ[(#^2 + 1)/2] &]^2 + 1 (* faster, _Giovanni Resta_, Jul 13 2015 *)
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Jul 12 2015, following a suggestion of R. P. Boas, May 19, 1974
%E Corrected and extended by _Ivan N. Ianakiev_, Jul 13 2015