A065592 Smallest prime beginning with exactly n 9's.

2, 97, 991, 99901, 99991, 9999901, 9999991, 999999929, 9999999929, 99999999907, 999999999937, 9999999999971, 99999999999923, 999999999999947, 9999999999999917, 99999999999999919, 99999999999999997, 9999999999999999919, 99999999999999999931

Offset

0,1

Links

M. F. Hasler, Table of n, a(n) for n = 0..200

Mathematica

fp[n_]:=Select[Join[10*n+{1, 7}, 100*n+Range[1, 99, 2]], PrimeQ, 1]; With[{ns=Table[FromDigits[PadRight[{}, n, 9]], {n, 20}]}, Join[{2}, Flatten[fp/@ns]]] (* Harvey P. Dale, May 12 2012 *)

Crossrefs

Cf. A037071, A065582, A065584 - A065591.

Sequence in context: A189313 A042151 A233192 * A233767 A223936 A224083

Adjacent sequences: A065589 A065590 A065591 * A065593 A065594 A065595

Keyword

nonn,base

Author

Robert G. Wilson v, Nov 28 2001

Extensions

Corrected by Don Reble, Jan 17 2007

Offset corrected by Sean A. Irvine, Sep 06 2023

Status

approved