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A024621 Positions of nonprimes among the powers of primes (A000961). 1
1, 4, 7, 8, 11, 15, 16, 19, 24, 28, 33, 42, 43, 45, 54, 69, 71, 79, 87, 92, 118, 121, 137, 153, 171, 188, 199, 245, 248, 293, 314, 341, 360, 361, 364, 393, 446, 483, 526, 559, 605, 651, 699, 719, 750, 857, 894, 930, 935, 1050, 1079, 1215, 1305, 1348, 1436, 1479, 1514 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..57.

PROG

(PARI) lista(nn) = {vec = vector(nn, i, i); powpr = select((i->((omega(i)==1) || (i==1))), vec); for (i = 1, #powpr, if (! isprime(powpr[i]), print1(i, ", ")); ); } \\ Michel Marcus, Oct 02 2013

CROSSREFS

Complement of A024620.

Sequence in context: A188376 A137362 A190765 * A296029 A000606 A215458

Adjacent sequences:  A024618 A024619 A024620 * A024622 A024623 A024624

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified April 17 03:44 EDT 2021. Contains 343059 sequences. (Running on oeis4.)