A080447 - OEIS

A080447

a(1) = 3, a(n) = smallest (nontrivial) multiple of a(n-1) containing n digits, a(n) not equal to 10*a(n-1).

3, 12, 108, 1188, 10692, 117612, 1058508, 11643588, 104792292, 1152715212, 10374436908, 114118805988, 1027069253892, 11297761792812, 101679856135308, 1118478417488388, 10066305757395492, 110729363331350412

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..18.

FORMULA

a(n) = A080446(n) for n>=2. - R. J. Mathar, Jul 10 2026

MATHEMATICA

ntm[n_]:=Module[{c=Ceiling[10^IntegerLength[n]/n]}, If[c==10, n(c+1), c n]]; NestList[ ntm, 3, 20] (* Harvey P. Dale, Aug 21 2022 *)

CROSSREFS

Cf. A080445, A080446, A080448, A080449, A080450, A080451, A080452, A080453.

Sequence in context: A377578 A111485 A293126 * A127059 A178013 A068099

Adjacent sequences: A080444 A080445 A080446 * A080448 A080449 A080450

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Feb 23 2003

EXTENSIONS

More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003

STATUS

approved