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A209931 Numbers n such that smallest digit of all divisors of n is 1. 1
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 71, 72, 73, 74, 75, 76, 77 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also numbers n such that smallest digit of concatenation of all divisors of n (A037278 or A176558) is 1.

Sequence is not the same as A052382, first deviation is at a(175): A052382(175) = 214, a(175) = 215.

Sequence is not the same as A067251, first deviation is at a(91): A067251 (91) = 101, a(91) = 111.

Complement of A209932.

LINKS

Table of n, a(n) for n=1..70.

EXAMPLE

Number  24 is in sequence because smallest digit of all divisors of 24 (1, 2, 4, 8, 3, 6, 12, 24) is 1.

CROSSREFS

Cf. A052382, A067251, A209929 (smallest digit of all divisors of n).

Sequence in context: A171397 A043095 A023804 * A067251 A052382 A055572

Adjacent sequences:  A209928 A209929 A209930 * A209932 A209933 A209934

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, Mar 20 2012

STATUS

approved

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Last modified December 16 01:43 EST 2019. Contains 330013 sequences. (Running on oeis4.)