

A236769


Numbers n such that lpf(2^n 1) < lpf(2^lpf(n) 1).


3



55, 77, 161, 169, 221, 275, 299, 323, 377, 385, 391, 437, 481, 493, 539, 551, 559, 605, 611, 629, 689, 697, 703, 715, 731, 779, 793, 799, 817, 847, 893, 901, 923, 935, 949, 1001, 1007, 1027, 1045, 1073, 1079, 1121, 1127, 1147, 1159, 1241, 1265, 1271, 1273, 1309
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OFFSET

1,1


COMMENTS

The numbers n for which A049479(n) < A049479(lpf(n)), where lpf(n) = A020639(n). All other n satisfy the equality (in particular all primes).
All terms are odd and composite.  Chai Wah Wu, Oct 04 2019


LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..111


PROG

(PARI) lpf(n) = vecmin(factor(n)[, 1]);
lista() = {my(vlpfmp = readvec("A049479.log")); for (i=2, #vlpfmp, if (vlpfmp[i] < vlpfmp[lpf(i)], print1(i, ", ")); ); } \\ Michel Marcus, Jan 31 2014


CROSSREFS

Cf. A049479 (a question in the third comment).
Sequence in context: A050781 A060260 A152080 * A119224 A135984 A140377
Adjacent sequences: A236766 A236767 A236768 * A236770 A236771 A236772


KEYWORD

nonn,more


AUTHOR

Thomas Ordowski, Jan 31 2014


EXTENSIONS

More terms from Michel Marcus, Jan 31 2014
More terms from Chai Wah Wu, Oct 04 2019


STATUS

approved



