

A167189


Larger prime power associated with record gap in A167186.


2



4, 8, 16, 25, 49, 121, 169, 243, 512, 1331, 1681, 2809, 4913, 6241, 7921, 9409, 14641, 22201, 36481, 44521, 49729, 94249, 185761, 226981, 271441, 292681, 452929, 619369, 769129, 822649, 1181569, 1852321, 5442889, 6265009, 8994001, 10883401, 17648401, 18722929
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OFFSET

1,1


LINKS

Donovan Johnson, Table of n, a(n) for n = 1..200


EXAMPLE

49 is in the sequence since the gap between it the previous prime power, 32, is greater than any previous gap.


PROG

(PARI) isA025475(n) = (omega(n) == 1 & !isprime(n))  (n == 1)
d_max=0; n_prev=1; for(n=2, 32e6, if(isA025475(n), d=nn_prev; if(d>d_max, print(n); d_max=d); n_prev=n))


CROSSREFS

Smaller prime power is in A167188.
Record gaps between nonprime prime powers: A167186.
Gaps between nonprime prime powers: A053707.
List of nonprime prime powers: A025475.
Sequence in context: A003451 A277029 A013934 * A050470 A138501 A096296
Adjacent sequences: A167186 A167187 A167188 * A167190 A167191 A167192


KEYWORD

nonn


AUTHOR

Michael B. Porter, Nov 01 2009


STATUS

approved



