

A071312


Squarefree numbers such that the largest prime factor = sum of other prime factors.


0



30, 70, 286, 646, 1798, 3135, 3526, 3570, 6279, 7198, 8855, 8970, 10366, 10626, 10695, 11571, 16095, 16530, 17255, 17391, 20615, 20706, 20735, 20806, 23326, 24738, 24882, 26691, 28083, 31031, 36519, 36890, 38086, 38130, 41151, 41615
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OFFSET

1,1


COMMENTS

If n = p(1)*p(2)*...p(r) is in the sequence, where p(r) is the largest prime factor, then p(r) = p(1)+p(2)+...+p(r1)


LINKS

Table of n, a(n) for n=1..36.


EXAMPLE

20706 = 2.3.7.17.29 and 2+3+7+17 = 29 hence 20706 is in the sequence


PROG

(PARI) for(n=2, 100000, if(issquarefree(n)*sum(i=1, omega(n)1, component(component(factor(n), 1), i))==vecmax(factor(n, 1)), print1(n, ", ")))


CROSSREFS

Cf. A071141.
Sequence in context: A131647 A301900 A071141 * A071142 A218327 A259753
Adjacent sequences: A071309 A071310 A071311 * A071313 A071314 A071315


KEYWORD

easy,nonn


AUTHOR

Benoit Cloitre, Jun 11 2002


STATUS

approved



