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A071964 Numbers n such that n = Lpf(n)*Lpf(phi(n)) where Lpf(x) = A006530(x) is the largest prime factor of x. 0
4, 6, 9, 10, 21, 25, 34, 39, 49, 55, 57, 111, 121, 155, 169, 203, 205, 219, 253, 289, 291, 301, 305, 327, 361, 489, 497, 505, 514, 529, 579, 689, 737, 755, 791, 841, 889, 905, 961, 979, 1027, 1081, 1205, 1255, 1299, 1355, 1369, 1379, 1461, 1477, 1681, 1703 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..52.

PROG

(PARI) for(n=1, 3000, if(vecmax(component(factor(n), 1))*vecmax(component(factor(eulerphi(n)), 1))==n, print1(n, ", ")))

CROSSREFS

Sequence in context: A275197 A118778 A108635 * A135257 A118697 A118695

Adjacent sequences:  A071961 A071962 A071963 * A071965 A071966 A071967

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Jun 16 2002

STATUS

approved

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Last modified May 30 11:39 EDT 2020. Contains 334724 sequences. (Running on oeis4.)