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A253645
Primes p such that p^k is zeroless for k=0,...,5.
6
2, 3, 5, 13, 17, 23, 31, 137, 233, 337, 383, 719, 971, 1291, 1663, 1777, 3623, 6113, 12589, 15733, 15791, 17729, 22637, 44623, 48989, 61379, 65777, 72379, 82129, 91331, 99559, 132859, 133733, 163633, 226129, 239539, 346391, 352133, 394223, 415379, 428531, 485113, 518233, 546523
OFFSET
1,1
COMMENTS
These are the primes in A253644. This is a subsequence of A253110 (k<=4) and contains A253646 (k <= 6) as a subsequence.
Motivated by A253646, i.e., the observation that many small primes satisfy this condition for k <= 5 (52 terms below 10^6) but only very few satisfy it for k <= 6 (only 2 terms between 20 and 2*10^9).
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..5300 (first 1200 terms from Zak Seidov)
MATHEMATICA
Select[Prime[Range[46000]], Count[Flatten[IntegerDigits/@(#^Range[5])], 0] == 0&] (* Harvey P. Dale, Jan 13 2015 *)
PROG
(PARI) forprime(p=0, , forstep(k=5, 1, -1, vecmin(digits(p^k))||next(2)); print1(p", "))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Zak Seidov and M. F. Hasler, Jan 07 2015
STATUS
approved