A001731 - OEIS

A001731

a(n) is 9 written in base 10-n.

9, 10, 11, 12, 13, 14, 21, 100, 1001, 111111111

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

LINKS

MATHEMATICA

Append[Array[FromDigits@ IntegerDigits[9, 10 - #] &, 9, 0], FromDigits@ ConstantArray[1, 9]] (* Michael De Vlieger, Feb 02 2022 *)

PROG

(PARI) a(n) = if (n==9, 111111111, fromdigits(digits(9, 10-n), 10)); \\ Michel Marcus, Feb 02 2022

CROSSREFS

KEYWORD

fini,nonn,base,full

AUTHOR

EXTENSIONS

Corrected by Henry Bottomley, Nov 23 2000

STATUS

approved