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%I #8 Sep 14 2020 19:48:11
%S 0,1,15,16,65,80,81,175,240,255,256,369,544,609,624,625,671,1040,1105,
%T 1215,1280,1295,1296,1695,1776,2145,2320,2385,2400,2401,2465,2800,
%U 3439,3471,3840,4015,4080,4095,4096,4160,4641,5265,5904,5936,6095,6305,6480
%N Numbers expressible as the difference of two nonnegative fourth powers.
%C Contains A000583 and A147857 as subsequences. - Chandler
%H Charles R Greathouse IV, <a href="/A152044/b152044.txt">Table of n, a(n) for n = 1..10000</a>
%e E.g. 15=2^4-1^4, 175=4^4-3^4
%t Select[Abs[Differences/@Tuples[Range[0,12]^4,2]]//Flatten//Union,#<= 6500&] (* _Harvey P. Dale_, Sep 14 2020 *)
%o (PARI) is(n)=if(n<1,return(!n)); for(m=sqrtnint(n-1,4)+1, sqrtnint(n\4,3)+1, if(ispower(m^4-n,4),return(1))); 0 \\ _Charles R Greathouse IV_, Sep 04 2013
%o (PARI) lst(lim)=my(v=List([0]),t); lim\=1; for(n=1,sqrtnint(lim\4,3)+1, for(m=sqrtnint(max(n^4-lim,0),4), n-1, t=n^4-m^4; if(t<=lim, listput(v,t)))); vecsort(Vec(v),,8) \\ _Charles R Greathouse IV_, Sep 04 2013
%Y Cf. A042965, A152043, A152045.
%K nonn
%O 1,3
%A Mark Taggart (mt2612f(AT)aol.com), Nov 21 2008
%E Extended by _Ray Chandler_, Dec 04 2008
%E Definition corrected by _Harvey P. Dale_, Jan 19 2018
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