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A088639 Smallest prime beginning with at least n n's (in decimal notation). 3


%S 2,11,223,3331,44449,555557,66666629,777777701,888888883,99999999907,

%T 1010101010101010101039,11111111111111111111111,

%U 12121212121212121212121223,1313131313131313131313131301

%N Smallest prime beginning with at least n n's (in decimal notation).

%H M. F. Hasler, <a href="/A088639/b088639.txt">Table of n, a(n) for n=0,...,100</a>.

%o (PARI) A088639(n)={ local(p=10^#Str(n),d=1); n*=(p^n-1)/(p-1); until( (d*=10)*(n+1)>p=nextprime(n*d), );p} /* M. F. Hasler, Jan 13 2009 */

%Y Cf. A088640. See A068120 for another version. See also A065584 - A065592.

%K base,easy,nonn

%O 0,1

%A _Amarnath Murthy_, Oct 27 2003

%E More terms from _Ray Chandler_, Nov 01 2003

%E PARI code, b-file, more cross-references and initial term added by _M. F. Hasler_, Jan 13 2009

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Last modified December 14 22:42 EST 2019. Contains 329987 sequences. (Running on oeis4.)