OFFSET
1,1
COMMENTS
A245575(a(n)) = 0.
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
MATHEMATICA
qsQ[n_] := qsQ[n] = With[{s = Sqrt[n]}, Which[IntegerQ[s], True, n == Floor[s] (Floor[s] + 1), True, True, False]];
A245575[n_] := Count[Range[0, n], k_ /; qsQ[k] && qsQ[n - k]];
Flatten[Position[Array[A245575, 1000, 0], 0]] - 1 (* Jean-François Alcover, May 08 2017 *)
PROG
(Haskell)
a245585 n = a245585_list !! (n-1)
a245585_list = filter ((== 0) . a245575) [0..]
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 04 2014
STATUS
approved