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A075002 a(n) = smallest k such that A007908(k) is divisible by n. 2
1, 2, 2, 2, 5, 2, 11, 6, 8, 10, 106, 2, 11, 22, 5, 6, 21, 8, 27, 20, 11, 106, 33, 6, 25, 30, 26, 24, 31, 20, 46, 6, 113, 64, 45, 36, 21, 64, 11, 20, 3, 24, 19, 128, 35, 68, 8, 6, 53, 50, 21, 120, 83, 26, 135, 128, 27, 82, 104, 20 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Conjecture: For every n, a(n) is well-defined.

The maximum of the first 10000 terms is a(6314) = 1002902 and A007908(1002902) is a 5902910-digit number. - Rick L. Shepherd, Oct 11 2015

LINKS

Rick L. Shepherd, Table of n, a(n) for n = 1..10000

EXAMPLE

a(4) = 2 since A007908(2)=12 is divisible by 4.

a(7) = 11 as 7 divides A007908(11)=1234567891011 and 7 does not divide any smaller concatenations.

PROG

(PARI) a(n)=my(m=Mod(1, n), k=1); while(m, m=10^#Str(k++)*m+k); k \\ Charles R Greathouse IV, Oct 11 2015

CROSSREFS

Cf. A007908.

Sequence in context: A029662 A077913 A069862 * A228917 A061311 A174960

Adjacent sequences:  A074999 A075000 A075001 * A075003 A075004 A075005

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Sep 01 2002

EXTENSIONS

More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 19 2003

Edited by Max Alekseyev, Sep 30 2015

STATUS

approved

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Last modified June 20 05:01 EDT 2019. Contains 324229 sequences. (Running on oeis4.)