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%I #13 Mar 14 2015 12:03:13
%S 82,626,706,1921,2402,4097,6497,6817,7186,8962,10001,10081,14642,
%T 17042,18737,20737,21202,21361,23137,24641,28562,28642,29186,29857,
%U 35377,38417,38497,43202,44977,50641,53026,53057,65266,67937,72097,83522,83602,84146,84817,85922
%N Quartan semiprimes: semiprimes of the form x^4 + y^4, x>0, y>0.
%C This is to A002645 as A001358 semiprimes is to A000040 primes.
%D George Greaves, On the representation of a number as a sum of two fourth powers, MATHEMATISCHE ZEITSCHRIFT, Volume 94, Number 3 (1966), 223-234, DOI: 10.1007/BF01111351.
%H Charles R Greathouse IV, <a href="/A182277/b182277.txt">Table of n, a(n) for n = 1..10000</a>
%F A001358 INTERSECTION A003336.
%e a(1) = 3^4 + 1^4 = 82 = 2 * 41.
%o (PARI) issemi(n)=bigomega(n)==2
%o list(lim)=my(v=List(),t);for(x=1,(lim+.5)^(1/4),for(y=1,min(x,(lim-x^4 + .5)^(1/4)),if(issemi(t=x^4+y^4),listput(v,t))));vecsort(Vec(v),,8) \\ _Charles R Greathouse IV_, Apr 22 2012
%Y Cf. A003336 Numbers that are the sum of 2 nonzero 4th powers, A002645 Quartan primes: primes of the form x^4 + y^4, x>0, y>0.
%K nonn
%O 1,1
%A _Jonathan Vos Post_, Apr 22 2012
%E a(12)-a(40) from _Charles R Greathouse IV_, Apr 22 2012
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