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A096843
Primes of form repdigit - 1. Primes whose sum of divisors is a decimal repdigit.
2
2, 3, 5, 7, 43, 443, 887, 2221, 8887, 444443, 888887, 444444443, 888888887, 444444444443, 888888888887, 222222222222222221, 444444444444444444444444444443, 44444444444444444444444444444443
OFFSET
1,1
COMMENTS
Union numbers 2, 5 and sequences A093171, A093163 and A091189.
Corresponding values of sigma(a(n)) are in A028987. - Jaroslav Krizek, Mar 19 2013
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..33 (terms < 10^1000)
EXAMPLE
n=43: sigma(43)=44;
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Labos Elemer, Jul 15 2004
EXTENSIONS
Missing a(1)=2 and a(3)=5 added by Jaroslav Krizek, Mar 19 2013
STATUS
approved