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%I #17 Mar 09 2016 03:09:04
%S 6,669,2456,5642,8255,15855,50704,63752,82621,112384,1151884,1191025,
%T 1203999,1228825,1244256,1459371,1661343,1819141,2264191,2445632,
%U 2451193,2812562,2875250,3425382,3792000,4866303,5123958,5587967
%N Integers n such that A000330(n) is the sum of 2 positive cubes.
%C Corresponding square pyramidal numbers are 91, 100029995, 4941161316, 59881606785, 187546467680, 1328674410280, ...
%e 6 is a term because A000330(6) = 91 = 3^3 + 4^3.
%o (PARI) isA003325(n) = for(k=1, sqrtnint(n\2, 3), ispower(n-k^3, 3) && return(1));
%o for(n=0, 1e7, if(isA003325(n*(n+1)*(2*n+1)/6), print1(n, ", ")));
%Y Cf. A000330, A003325.
%K nonn
%O 1,1
%A _Altug Alkan_, Mar 06 2016
%E a(11)-a(28) from _Chai Wah Wu_, Mar 08 2016
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