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Primes within A186278.
0

%I #11 Oct 06 2018 01:52:15

%S 37,43,73,79,109,127,139,181,229,241,271,277,313,331,349,367,397,421,

%T 433,457,487,547,571,577,607,613,673,691,727,733,751,757,769,823,829,

%U 853,907,919,991,1009,1063,1087,1093,1117,1123,1171,1231,1249,1279

%N Primes within A186278.

%e 367 is in the sequence because (1) it is prime and (2) the sum of its digits (3 + 6 + 7 = 16) plus the sum of the digits of 367^2 (134689 -> 1 + 3 + 4 + 6 + 8 + 9 = 31) equals 16 + 31 = 47, which is prime.

%t Select[Prime[Range[300]], PrimeQ[Total[IntegerDigits[#]]+Total[IntegerDigits[#^2]]]&]

%Y Cf. A186278, A186279, A186280.

%K nonn,easy,base

%O 1,1

%A _Harvey P. Dale_, Feb 16 2011