OFFSET
1,5
COMMENTS
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..15
EXAMPLE
1^2 + 4^2 + 19^2 + 379^2 = 144019.
MATHEMATICA
RecurrenceTable[{a[1] == a[2] == a[3] == a[4] == 1, a[n] == a[n-1]^2 + a[n-2]^2 + a[n-3]^2 + a[n-4]^2}, a, {n, 15}] (* Vincenzo Librandi, Aug 21 2016 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Jan 02 2006
STATUS
approved