OFFSET
1,1
COMMENTS
Basis for sequence is shortest arithmetic series with initial term 1 and difference n that sums to a perfect square.
EXAMPLE
a(3)=241 since 1 + 4 + 7 +...+ 241 = 99^2 = 9801 and no other arithmetic series with initial term 1, difference 3 and fewer terms sums to a perfect square.
CROSSREFS
KEYWORD
nonn
AUTHOR
Charlie Marion, Nov 21 2004
STATUS
approved