A095229 - OEIS

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A095229

a(1) = 1; a(n) = n multiplied by the concatenation of all previous terms.

0

1, 2, 36, 4944, 61824720, 7418966770948320, 86554612327730451932767396638240, 9891955694597765935173416758656692436898621843615462139173105920

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OFFSET

1,2

COMMENTS

a(n) >= 10^(2^(n-2)-1) (can be easily shown by induction).

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

Let n = 4. The previous terms are 1,2 and 36. Their concatenation is 1236. This number is multiplied by 4 and we get a(4) = 4944.

MATHEMATICA

a = {1}; For[n=2, n<10, n++, AppendTo[a, n*FromDigits[Flatten[IntegerDigits[a]]]]]; a

CROSSREFS

Sequence in context: A203021 A319507 A001070 * A047832 A004003 A369676

Adjacent sequences: A095226 A095227 A095228 * A095230 A095231 A095232

KEYWORD

base,nonn,less

AUTHOR

Amarnath Murthy, Jun 11 2004

EXTENSIONS

Edited, corrected and extended by Stefan Steinerberger, Jun 16 2007

STATUS

approved