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A039990 k th digit of a(n) is the number of different digits within 4 of k (not including k). 0
111, 122, 212, 221, 1111, 1222, 2122, 2212, 2221, 11111, 12222, 21222, 22122, 22212, 22221, 111111, 122221, 212222, 221222, 222122, 222212 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..20.

CROSSREFS

Sequence in context: A280635 A280732 A280636 * A034840 A135643 A070798

Adjacent sequences:  A039987 A039988 A039989 * A039991 A039992 A039993

KEYWORD

base,easy,nonn

AUTHOR

Erich Friedman

STATUS

approved

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Last modified December 16 06:18 EST 2019. Contains 330016 sequences. (Running on oeis4.)