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A052424 Numbers with no single-digit factors (apart from 1 and n). 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..59.

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

Adjacent sequences:  A052421 A052422 A052423 * A052425 A052426 A052427

KEYWORD

nonn,base

AUTHOR

Henry Bottomley, Mar 14 2000

STATUS

approved

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Last modified February 22 15:52 EST 2019. Contains 320399 sequences. (Running on oeis4.)