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%I A133561
%S A133561 3,5,6,8,9,10,14,18,19,20,21,26,32,34,37,38,39,41,44,47,49,52,53,54,59,
%T A133561 60,63,64,66,68,70,71,75,83,88,89,91,92,97,100,107,108,110,112,113,117,
%U A133561 122,125,128,129,131,135,141,142,150,151,157,158,165,168,169,178,183
%N A133561 Numbers n for which sum of squares of seven consecutive primes(n,n+1,
               n+2,n+3,n+4,n+5,n+6) is prime.
%C A133561 For sum of squares of two consecutive primes only 2^2+3^2=13 is prime. 
               For sum of squares of three consecutive primes A133529 seems that 
               only 83 belonging(checked for all n<1000000). Sums of squares of 
               four (and all even number) of consecutive primes are even numbers 
               with exception n=1 but 2^2+3^2+5^2+7^2=87=3*29 is not prime. Sums 
               of squares of five of consecutive primes A133559. Sums of squares 
               of seven of consecutive primes A133562
%e A133561 a(3)=6 because Prime[6]^2+Prime[7]^2+Prime[8]^2+Prime[9]^2+Prime[10]^2+Prime[11]^2+Prime[12]^2=
%e A133561 13^2+17^2+19^2+23^2+29^2+31^2+37^2=4519 is prime
%t A133561 b = {}; a = 2; Do[k = Prime[n]^a + Prime[n + 1]^a + Prime[n + 2]^a + 
               Prime[n + 3]^a + Prime[n + 4]^a + Prime[n + 5]^a + Prime[n + 6]^a; 
               If[PrimeQ[k], AppendTo[b, n]], {n, 1, 100}]; b {*Artur Jasinski*)
%Y A133561 Cf. A133538, A133558, A133559, A133561.
%Y A133561 Sequence in context: A026430 A002150 A153264 this_sequence A095117 A089585 
               A121506
%Y A133561 Adjacent sequences: A133558 A133559 A133560 this_sequence A133562 A133563 
               A133564
%K A133561 nonn
%O A133561 1,1
%A A133561 Artur Jasinski (grafix(AT)csl.pl), Sep 16 2007

    
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Last modified December 9 14:43 EST 2009. Contains 170430 sequences.


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