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A068822 a(n) = gcd(n,c(n)), where c(n) is the 10's complement of n. 4
1, 2, 1, 2, 5, 2, 1, 2, 1, 10, 1, 4, 1, 2, 5, 4, 1, 2, 1, 20, 1, 2, 1, 4, 25, 2, 1, 4, 1, 10, 1, 4, 1, 2, 5, 4, 1, 2, 1, 20, 1, 2, 1, 4, 5, 2, 1, 4, 1, 50, 1, 4, 1, 2, 5, 4, 1, 2, 1, 20, 1, 2, 1, 4, 5, 2, 1, 4, 1, 10, 1, 4, 1, 2, 25, 4, 1, 2, 1, 20, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..9999

FORMULA

a(n) = gcd(n,A089186(n)) = gcd(n,A178914(n)). - Alois P. Heinz, Nov 05 2018

EXAMPLE

a(45) = 5 as 10's complement of 45 is 100-45 = 55 and (45,55) = 5.

MAPLE

a:=n-> igcd((10^length(n)-n), n):

seq(a(n), n=1..100);  # Alois P. Heinz, Sep 22 2015

MATHEMATICA

GCD[#, 10^(IntegerLength[#]) - #] & /@ Range[82] (* Jayanta Basu, Aug 07 2013 *)

CROSSREFS

Cf. A089186, A178914.

Sequence in context: A135506 A295516 A330209 * A337224 A090079 A165195

Adjacent sequences:  A068819 A068820 A068821 * A068823 A068824 A068825

KEYWORD

nonn,base,easy

AUTHOR

Amarnath Murthy, Mar 08 2002

STATUS

approved

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Last modified November 29 22:54 EST 2020. Contains 338779 sequences. (Running on oeis4.)