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%I #15 Sep 04 2023 16:37:06
%S 2,3,9,10,11,16,18,25,26,28,31,33,36,42,43,46,47,54,56,58,63,68,76,87,
%T 91,93,99,101,105,106,114,127,131,145,153,159,183,186,196,201,206,229,
%U 230,232,233,238,239,241,244,245,246,248,253,256,257,264,265,266,268
%N Numbers k for which the sum of squares of five consecutive primes starting with prime(k) is prime (A133559).
%C For sums of squares of two consecutive primes, only k=1 yields a prime.
%C For sums of squares of three consecutive primes A133529, it seems that only k=2 yields a prime (checked for all k < 1000000).
%C Sums of squares of four (and all even numbers of) consecutive primes are even numbers except at k=1.
%e a(1)=2 because prime(2)^2 + prime(3)^2 + prime(4)^2 + prime(5)^2 + prime(6)^2 = 3^2 + 5^2 + 7^2 + 11^2 + 13^2 = 373 is prime.
%t b = {}; a = 2; Do[k = Prime[n]^a + Prime[n + 1]^a + Prime[n + 2]^a + Prime[n + 3]^a + Prime[n + 4]^a; If[PrimeQ[k], AppendTo[b, n]], {n, 1, 100}]; b (* _Artur Jasinski_ *)
%Y Cf. A133538, A133559.
%K nonn
%O 1,1
%A _Artur Jasinski_, Sep 16 2007
%E Name and example corrected by _Jonathan Sondow_, Nov 04 2015