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A255744
a(1) = 1; for n > 1, a(n) = 10*9^(A000120(n-1)-1).
5
1, 10, 10, 90, 10, 90, 90, 810, 10, 90, 90, 810, 90, 810, 810, 7290, 10, 90, 90, 810, 90, 810, 810, 7290, 90, 810, 810, 7290, 810, 7290, 7290, 65610, 10, 90, 90, 810, 90, 810, 810, 7290, 90, 810, 810, 7290, 810, 7290, 7290, 65610, 90, 810, 810, 7290, 810, 7290
OFFSET
1,2
COMMENTS
Also, this is a row of the square array A255740.
Partial sums give A255765.
LINKS
EXAMPLE
Also, written as an irregular triangle in which the row lengths are the terms of A011782, the sequence begins:
1;
10;
10, 90;
10, 90, 90, 810;
10, 90, 90, 810, 90, 810, 810, 7290;
...
MATHEMATICA
MapAt[Floor, Array[10*9^(DigitCount[# - 1, 2, 1] - 1) &, 54], 1] (* Michael De Vlieger, Nov 03 2022 *)
PROG
(PARI) a(n) = if (n==1, 1, 10*9^(hammingweight(n-1)-1)); \\ Michel Marcus, Mar 15 2015
KEYWORD
nonn
AUTHOR
Omar E. Pol, Mar 05 2015
EXTENSIONS
More terms from Michel Marcus, Mar 15 2015
STATUS
approved