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A102252 Slowest increasing sequence beginning with 1 whose digits satisfy the rule d*2. 0
1, 2, 4, 8, 16, 21, 24, 248, 481, 681, 6212, 16212, 42421, 242484, 842484, 8168168, 48168162, 121621216, 816212162, 1242421242, 4212162124, 24212424848, 42484842421, 242484842484, 816816848168, 1684842484816, 8168481681621 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Same digits as A061581.

LINKS

Table of n, a(n) for n=1..27.

FORMULA

d*2, beginning with 1.

EXAMPLE

Read a(5)=16, which produces first digit of a(6)=2 because 1*2=2 and second digit of a(6)=1 and first digit of a(7)=2 because 6*2=12.

MATHEMATICA

t = Flatten[ NestList[ Function[x, Flatten[ IntegerDigits[2IntegerDigits[ x]]]], 1, 17]]; a = 0; l = {}; Do[k = 1; While[fd = FromDigits[ Take[t, k]]; a >= fd, k++ ]; t = Drop[t, k]; AppendTo[l, fd]; a = fd, {n, 27}]; l (* Robert G. Wilson v, Feb 21 2005 *)

CROSSREFS

Cf. A061581.

Sequence in context: A134162 A244484 A045776 * A174838 A196871 A001856

Adjacent sequences:  A102249 A102250 A102251 * A102253 A102254 A102255

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 19 07:51 EST 2019. Contains 320309 sequences. (Running on oeis4.)