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%I #17 Mar 21 2018 18:21:49
%S 11,211,3111,41111,511111,6111111,71111111,811111111,9111111111,
%T 101111111111,1111111111111,12111111111111,131111111111111,
%U 1411111111111111,15111111111111111,161111111111111111,1711111111111111111,18111111111111111111,191111111111111111111
%N n followed by n 1's.
%D J. Earls, On Smarandache Repunit N Numbers, Smarandache Notions Journal (2004), Vol. 14.1, pp 251-258.
%F a(n) = n*10^n+(10^n-1)/9.
%F G.f.: x*(11-20*x)/((1-x)*(1-20*x+100*x^2)). a(n)=20*a(n-1)-100*a(n-2)-9, n>1. - _Michael Somos_, Oct 29, 2002
%p A075858:=n->n*10^n+(10^n-1)/9; seq(A075858(n), n=1..50); # _Wesley Ivan Hurt_, Nov 23 2013
%t Table[n*10^n+(10^n-1)/9, {n,50}] (* _Wesley Ivan Hurt_, Nov 23 2013 *)
%o (PARI) a(n)=if(n<1,0,n*10^n+(10^n-1)/9)
%Y Cf. A068817.
%K easy,nonn,less
%O 1,1
%A _Jason Earls_, Oct 15 2002
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