cp's OEIS Frontend

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.

A134616 Numbers such that the sum of squares of their prime factors (taken with multiplicity) is a prime.

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%I A134616 #10 Apr 09 2025 20:24:56
%S A134616 6,10,12,14,26,34,40,45,54,56,63,74,75,80,90,94,96,99,104,105,126,134,
%T A134616 146,147,152,153,171,176,184,194,206,207,231,232,234,250,261,273,274,
%U A134616 296,300,306,326,328,334,342,344,345,350,357,363,369,376,384,386,387
%N A134616 Numbers such that the sum of squares of their prime factors (taken with multiplicity) is a prime.
%H A134616 Hieronymus Fischer, <a href="/A134616/b134616.txt">Table of n, a(n) for n = 1..10000</a>
%e A134616 a(2)=10, since 10=2*5 and 2^2+5^2=29 which is prime.
%t A134616 f[{a_,b_}]:=Table[a,b];Select[Range[2,387],PrimeQ[ Total[Flatten[(f/@FactorInteger[#])^2]] ]&] (* _James C. McMahon_, Apr 09 2025 *)
%Y A134616 Cf. A001597, A025475, A134333, A134344, A134376.
%Y A134616 Cf. A134600, A134602, A134605, A134608, A134612, A134619, A134621.
%K A134616 nonn
%O A134616 1,1
%A A134616 _Hieronymus Fischer_, Nov 11 2007
%E A134616 Minor edits by the author, May 06 2013