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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
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
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 A373944 A218338
KEYWORD
base,easy,nonn
AUTHOR
EXTENSIONS
More terms from Robert G. Wilson v, Feb 21 2005
STATUS
approved