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A073844 a(1) = 1, a(n) = largest prime divisor of A057137(n). 1
1, 3, 41, 617, 823, 643, 9721, 14593, 3803, 3803, 14405693, 10288065751, 116216501, 12079920647, 7552031, 435503, 1763668414462081, 106377431, 27961, 27961, 205126079, 84225392753, 7347135846537257, 437274720469, 12792129877, 244251294564157 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Daniel Suteu, Table of n, a(n) for n = 1..167

FORMULA

a(n) = A006530(A057137(n)). - Michel Marcus, May 26 2022

PROG

(PARI) a(n) = if(n==1, 1, vecmax(factor(sum(i=1, n, i%10*10^(n-i)))[, 1])); \\ Daniel Suteu, May 25 2022

CROSSREFS

Cf. A006530, A057137.

Sequence in context: A213378 A189356 A155672 * A138961 A075022 A300281

Adjacent sequences: A073841 A073842 A073843 * A073845 A073846 A073847

KEYWORD

nonn

AUTHOR

Jason Earls, Sep 02 2002

STATUS

approved

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Last modified November 28 22:51 EST 2022. Contains 358421 sequences. (Running on oeis4.)