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A121042 Smallest divisor of n that is also contained in the decimal representation of n. 2
1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 23, 2, 5, 2, 27, 2, 29, 3, 1, 2, 3, 34, 5, 3, 37, 38, 3, 4, 1, 2, 43, 4, 5, 46, 47, 4, 49, 5, 1, 2, 53, 54, 5, 56, 57, 58, 59, 6, 1, 2, 3, 4, 5, 6, 67, 68, 69, 7, 1, 2, 73, 74, 5, 76, 7, 78, 79, 8, 1, 2, 83, 4, 5, 86, 87, 8, 89, 9, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

1 <= a(n) <= n;

a(A011531(n)) = 1; a(n) = n iff A121041(n) = 1.

a(n) = 1 for almost all n (measure 1). - Charles R Greathouse IV, Mar 31 2016

LINKS

Table of n, a(n) for n=1..91.

EXAMPLE

a(48) = Min{4, 8, 48} = 4;

a(49) = Min{49} = 49;

a(120) = Min{1, 2, 12, 20, 120} = 1;

a(121) = Min{1} = 1.

PROG

(PARI) substr(a, b)=a=digits(a); b=digits(b); for(i=0, #a-#b, for(j=1, #b, if(a[i+j]!=b[j], next(2))); return(1)); 0

a(n)=fordiv(n, d, if(substr(n, d), return(d))) \\ Charles R Greathouse IV, Mar 31 2016

CROSSREFS

Sequence in context: A256229 A052423 A126616 * A000030 A179635 A216587

Adjacent sequences:  A121039 A121040 A121041 * A121043 A121044 A121045

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Jul 21 2006

STATUS

approved

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Last modified October 16 04:02 EDT 2018. Contains 316259 sequences. (Running on oeis4.)