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A102251 Begin with 1, multiply each digit by 2. 3
1, 2, 4, 8, 16, 2, 12, 4, 2, 4, 8, 4, 8, 16, 8, 16, 2, 12, 16, 2, 12, 4, 2, 4, 2, 12, 4, 2, 4, 8, 4, 8, 4, 2, 4, 8, 4, 8, 16, 8, 16, 8, 4, 8, 16, 8, 16, 2, 12, 16, 2, 12, 16, 8, 16, 2, 12, 16, 2, 12, 4, 2, 4, 2, 12, 4, 2, 4, 2, 12, 16, 2, 12, 4, 2, 4, 2, 12, 4, 2, 4, 8, 4, 8, 4, 2, 4, 8, 4, 8, 4, 2, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Same digits as A061581 without the memory of the groupings of the preceding digits. A bunch of sequences can be produced with this rule: a(n)=d*k beginning with 1,2,3... for k=2,3,...

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

FORMULA

d*2, beginning with 1

EXAMPLE

Read a(5)=16 which produces a(6)=2 because 1*2=2 and a(7)=12 because 6*2=12. Now read a(6)=2 which produces [a(7) is already written] a(8)=4 because 2*2=4.

MATHEMATICA

Flatten[ NestList[ Function[x, Flatten[ FromDigits /@ 2IntegerDigits[ x]]], 1, 15]] (* Robert G. Wilson v, Feb 21 2005 *)

PROG

(Haskell)

a102251 n = a102251_list !! n

a102251_list = 1 : (map (* 2) $

concatMap (map (read . return) . show) a102251_list)

-- Reinhard Zumkeller, Oct 02 2014

CROSSREFS

Cf. A061581.

Cf. A248131.

Sequence in context: A110333 A247292 A069783 * A339853 A218338 A218468

Adjacent sequences: A102248 A102249 A102250 * A102252 A102253 A102254

KEYWORD

base,easy,nonn

AUTHOR

Alexandre Wajnberg and Eric Angelini, Feb 18 2005

EXTENSIONS

More terms from Robert G. Wilson v, Feb 21 2005

STATUS

approved

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Last modified February 6 05:07 EST 2023. Contains 360097 sequences. (Running on oeis4.)