A102254 - OEIS

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A102254

Begin with 3, multiply each digit by 2, keeping the memory of the groupings of the preceding digits.

3, 6, 12, 24, 48, 816, 16212, 212424, 424848, 84816816, 1681621216212, 21216212424212424, 424212424848424848, 8484248481681684816816, 1681684816816212162121681621216212, 21216212168162121621242421242421216212424212424

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..16.

FORMULA

d*2, beginning with 3.

EXAMPLE

Read a(3)=12 which produces a(4)=24 because 1*2=2 and 2*2=4.

MATHEMATICA

Flatten[ NestList[ Function[x, FromDigits[ Flatten[ IntegerDigits[2IntegerDigits[ x]]] ]], 3, 15]] (* Robert G. Wilson v, Feb 21 2005 *)

CROSSREFS