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A356021
Positive numbers k such that, for any consecutive prime numbers p, q <= A006530(n), the p-adic and q-adic valuations of n are different.
1
1, 2, 3, 4, 8, 9, 10, 12, 16, 18, 20, 21, 24, 27, 32, 40, 45, 48, 50, 54, 63, 64, 72, 75, 80, 81, 84, 90, 96, 100, 108, 110, 126, 128, 135, 144, 147, 160, 162, 168, 189, 192, 200, 220, 243, 250, 256, 270, 273, 288, 300, 320, 324, 336, 350, 360, 375, 378, 384
OFFSET
1,2
COMMENTS
Equivalently, these are fixed points of A356014.
This sequence is infinite as it contains A066205 and A066206.
If m is a term, then m^k is a term (for any k >= 0).
PROG
(PARI) is(n) = { my (v=-1); forprime (p=2, oo, if (n==1, return (1), v==v=valuation(n, p), return (0), n\=p^v)) }
CROSSREFS
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Jul 23 2022
STATUS
approved