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A052424
Numbers k with no single-digit factors (apart from 1 and k).
1
1, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 121, 127, 131, 137, 139, 143, 149, 151, 157, 163, 167, 169, 173, 179, 181, 187, 191, 193, 197, 199, 209, 211, 221, 223, 227, 229, 233, 239
OFFSET
1,2
PROG
(PARI) isok(n) = {d = divisors(n); for (i = 2, #d - 1, if (length(Str(d[i])) == 1, return (0)); ); return (1); } \\ Michel Marcus, Jul 27 2013
CROSSREFS
Cf. A008364.
Sequence in context: A110923 A137589 A301378 * A055398 A070159 A322394
KEYWORD
nonn,base
AUTHOR
Henry Bottomley, Mar 14 2000
STATUS
approved