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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A134620 Numbers such that the sum of 4th power of their prime factors is a prime.

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%I A134620 #16 May 21 2013 19:02:37
%S A134620 6,10,12,14,22,34,38,40,45,46,74,82,117,118,122,126,142,152,158,171,
%T A134620 194,231,262,278,296,345,358,363,376,384,387,429,432,446,454,458,482,
%U A134620 486,490,500,507,522,536,550,566,584,626,627,634,639,663,675,686,704,705
%N A134620 Numbers such that the sum of 4th power of their prime factors is a prime.
%C A134620 Prime factors must be taken with multiplicity. - _Harvey P. Dale_, May 23 2012
%C A134620 The calculation of higher terms is time-consuming, since for any number of the form 2*p with a prime number p > 10^5 the primality test have to be accomplished for a number > 10^20. - _Hieronymus Fischer_, May 21 2013
%H A134620 Harvey P. Dale and Hieronymus Fischer, <a href="/A134620/b134620.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Harvey P. Dale)
%e A134620 a(2) = 10, since 10 = 2*5 and 2^4+5^4 = 641 which is prime.
%e A134620 a(9) = 45, since 45 = 3*3*5 and 3^4+3^4+5^4 = 787 which is prime.
%e A134620 a(9883) = 333314, since 333314 = 3*166657 and 2^4+166657^4 = 771425941499397811217 which is prime.
%t A134620 Select[Range[1000],PrimeQ[Total[Flatten[Table[First[#],{Last[#]}]&/@ FactorInteger[#]]^4]]&] (* _Harvey P. Dale_, May 23 2012 *)
%Y A134620 Cf. A001597, A025475, A134333, A134344, A134376.
%Y A134620 Cf. A134600, A134602, A134605, A134608, A134612, A134616, A134618, A134621.
%K A134620 nonn
%O A134620 1,1
%A A134620 _Hieronymus Fischer_, Nov 11 2007