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A055256
Number of odd digits in 3^n.
2
1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 3, 5, 4, 5, 3, 4, 3, 5, 3, 4, 3, 5, 7, 6, 4, 3, 5, 7, 6, 6, 7, 9, 7, 10, 9, 11, 11, 10, 12, 11, 10, 11, 14, 12, 10, 11, 12, 12, 11, 14, 14, 17, 9, 13, 14, 16, 18, 12, 10, 15, 15, 13, 11, 15, 12, 19, 15, 18, 19, 19, 20, 20, 18, 19, 21, 20, 21, 22
OFFSET
0,7
LINKS
PROG
(PARI) a(n) = #select(x->((x%2) == 1), digits(3^n)); \\ Michel Marcus, Nov 22 2019
CROSSREFS
Sequence in context: A139821 A248972 A077563 * A369985 A295630 A029147
KEYWORD
nonn,base,easy
AUTHOR
Asher Auel, May 05 2000
STATUS
approved