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A133940
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Numbers n such that one-third of the sum of squares of three consecutive primes is prime (A084951).
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3
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4, 5, 8, 13, 15, 26, 46, 47, 50, 55, 57, 59, 61, 65, 66, 69, 77, 82, 89, 91, 94, 101, 105, 116, 134, 136, 137, 138, 144, 157, 194
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| With exception of the two first term all numbers in A133529 are divisible by 3
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EXAMPLE
| a(1)=4 because (Prime[4]^2 + Prime[5]^2 + Prime[6]^2)/3=113 is prime
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MATHEMATICA
| b = {}; a = 2; Do[k = (Prime[n]^a + Prime[n + 1]^a + Prime[n + 2]^a)/3; If[PrimeQ[k], AppendTo[b, n]], {n, 1, 200}]; b
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CROSSREFS
| Cf. A133529, A133940.
Sequence in context: A027975 A011980 A061765 * A174398 A030978 A101948
Adjacent sequences: A133937 A133938 A133939 * A133941 A133942 A133943
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KEYWORD
| nonn
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AUTHOR
| Artur Jasinski (grafix(AT)csl.pl), Sep 30 2007
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