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A238120
Powerful numbers of the form x^3 + y^3 with x and y coprime.
1
9, 3528, 12168, 51984, 207576, 450241, 711828, 798768, 1590121, 7154784, 8609599, 40589641, 95355225, 138393792, 244293408, 344157184, 726887051, 737461269, 1232922769, 1290821184, 1630544400, 1734139449, 2901360600, 3002319675, 3401256943, 4435426801, 4589212453
OFFSET
1,1
COMMENTS
Powerful numbers are n such that p | n -> p^2 | n for all primes p, see A001694.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..150
PROG
(PARI) list(lim)=my(v=List(), x3, t); for(x=1, sqrtnint(lim\1-1, 3), x3=x^3; for(y=1, x, if(gcd(x, y)>1, next); t=x3+y^3; if(t>lim, break); if(ispowerful(t), listput(v, t)))); Set(v)
CROSSREFS
Cf. A001694.
Sequence in context: A234145 A291547 A266458 * A229151 A162013 A222948
KEYWORD
nonn
AUTHOR
STATUS
approved