OFFSET
0,2
COMMENTS
FORMULA
a(n) = (b(n)^3+1)/7^n, n>=0, with b(n):=A212153(n) given by a recurrence. See also a Maple program for b(n) there.
EXAMPLE
a(0) = 1/1 = 1.
a(3) = (19^3 + 1)/7^3 = 6860/343 = 20, (b(3) = 19^7 (mod 7^3) = 19).
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, May 02 2012
STATUS
approved