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.

A051393 Numbers whose square is expressible as the difference of positive cubes in more than one way.

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%I A051393 #11 Oct 30 2013 04:39:08
%S A051393 36963,66248,157339,262808,295704,519841,529984,793117,990584,998001,
%T A051393 1258712,1271403,1291836,1788696,2102464,2365632,2688728,3294486,
%U A051393 3756536,4158728,4239872,4248153,4620375,5532247,5738904,5938947,6344936,6562101,7095816,7924672
%N A051393 Numbers whose square is expressible as the difference of positive cubes in more than one way.
%H A051393 Donovan Johnson, <a href="/A051393/b051393.txt">Table of n, a(n) for n = 1..100</a>
%e A051393 36963^2 = 1110^3-111^3 = 1332^3-999^3.
%o A051393 (PARI) mm=577350; cb=vector(mm); for(i=1, mm, cb[i]=i^3); v=vector(10^6); n=vector(10); c=0; mx=10^12; for(i=1, mm-1, for(j=i+1, mm, s=cb[j]-cb[i]; if(s<=mx, if(issquare(s,&r), v[r]++; if(v[r]==2, c++; n[c]=r)), next(2)))); n=vecsort(n); for(i=1, c, print1(n[i] ", ")) \\ _Donovan Johnson_, Oct 29 2013
%Y A051393 Cf. A038596, A038597.
%K A051393 nonn
%O A051393 1,1
%A A051393 _Jud McCranie_
%E A051393 Corrected and extended by _Ray Chandler_, Dec 01 2008
%E A051393 Offset corrected by _Donovan Johnson_, Oct 29 2013