OFFSET
0,1
COMMENTS
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..500
FORMULA
a(n) = (b(n)^2 + 1)/5^n, n>=0, with b(n) = A268922(n).
EXAMPLE
a(0) = (0 + 4)/1 = 4.
a(4) = (261^2 + 4)/5^4 = 109.
PROG
(PARI) a(n) = ((truncate(sqrt(-4+O(5^(n)))))^2 + 4)/5^n; \\ Michel Marcus, Mar 07 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Mar 02 2016
EXTENSIONS
Terms a(21) and beyond from Andrew Howroyd, Mar 02 2020
STATUS
approved