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A053379 a(n) contains n digits (either '7' or '8') and is divisible by 2^n. 0
8, 88, 888, 7888, 77888, 877888, 7877888, 87877888, 787877888, 8787877888, 88787877888, 888787877888, 8888787877888, 88888787877888, 788888787877888, 8788888787877888, 88788888787877888, 888788888787877888 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..18.

FORMULA

a(n)=a(n-1)+10^(n-1)*(8-[a(n-1)/2^(n-1) mod 2]) i.e. a(n) ends with a(n-1); if (n-1)-th term is divisible by 2^n then n-th term begins with an 8, if not then n-th term begins with a 7.

CROSSREFS

Cf. A023414, A050621, A050622, A035014.

Sequence in context: A053377 A053378 A062185 * A002282 A112907 A053380

Adjacent sequences:  A053376 A053377 A053378 * A053380 A053381 A053382

KEYWORD

base,nonn

AUTHOR

Henry Bottomley, Mar 06 2000

STATUS

approved

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Last modified May 30 18:38 EDT 2020. Contains 334728 sequences. (Running on oeis4.)