

A269842


Integers n such that A000330(n) is the sum of 2 positive cubes.


1



6, 669, 2456, 5642, 8255, 15855, 50704, 63752, 82621, 112384, 1151884, 1191025, 1203999, 1228825, 1244256, 1459371, 1661343, 1819141, 2264191, 2445632, 2451193, 2812562, 2875250, 3425382, 3792000, 4866303, 5123958, 5587967
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OFFSET

1,1


COMMENTS

Corresponding square pyramidal numbers are 91, 100029995, 4941161316, 59881606785, 187546467680, 1328674410280, ...


LINKS

Table of n, a(n) for n=1..28.


EXAMPLE

6 is a term because A000330(6) = 91 = 3^3 + 4^3.


PROG

(PARI) isA003325(n) = for(k=1, sqrtnint(n\2, 3), ispower(nk^3, 3) && return(1));
for(n=0, 1e7, if(isA003325(n*(n+1)*(2*n+1)/6), print1(n, ", ")));


CROSSREFS

Cf. A000330, A003325.
Sequence in context: A222743 A222720 A309597 * A046985 A159371 A159620
Adjacent sequences: A269839 A269840 A269841 * A269843 A269844 A269845


KEYWORD

nonn


AUTHOR

Altug Alkan, Mar 06 2016


EXTENSIONS

a(11)a(28) from Chai Wah Wu, Mar 08 2016


STATUS

approved



