OFFSET
0,1
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..10000
FORMULA
Define the sequence {b(n)} by the recurrence b(0) = 0 and b(1) = 9, b(n) = b(n-1) + 7 * (9 * b(n-1)^3 - 71) mod 10^n for n > 1, then a(n) = (b(n+1) - b(n))/10^n.
EXAMPLE
9^3 == 9 (mod 10).
39^3 == 19 (mod 10^2).
639^3 == 119 (mod 10^3).
8639^3 == 1119 (mod 10^4).
38639^3 == 11119 (mod 10^5).
238639^3 == 111119 (mod 10^6).
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 09 2019
STATUS
approved