login
A180273
Squares which are a sum of consecutive squares starting with 7^2.
3
49, 8464, 20449, 60025, 2304324, 3624882849
OFFSET
1,1
COMMENTS
That is, terms are squares of the form sum_{i=7..m} i^2 for some m. This sequence is complete. See A180442 and A184763.
EXAMPLE
a(2) = 8464 = 92^2 = 7^2+8^2+9^2+...+28^2+29^2.
MATHEMATICA
Select[Accumulate[Range[7, 3000]^2], IntegerQ[Sqrt[#]]&] (* Harvey P. Dale, Jul 16 2014 *)
PROG
(PARI) for(n=8, 9999999, t=n*(n+1)*(2*n+1)/6-91; if(issquare(t), print1(t, ", ")))
CROSSREFS
KEYWORD
nonn,easy,fini,full
AUTHOR
Zhining Yang, Jan 17 2011
STATUS
approved