A180498 a(n) = n^2 - 5*floor(n/sqrt(5))^2.

1, 4, 4, 11, 5, 16, 4, 19, 1, 20, 41, 19, 44, 16, 45, 11, 44, 4, 41, 80, 36, 79, 29, 76, 20, 71, 9, 64, 121, 55, 116, 44, 109, 31, 100, 16, 89, 164, 76, 155, 61, 144, 44, 131, 25, 116, 4, 99, 196, 80, 181, 59, 164, 36, 145, 11, 124, 239, 101, 220, 76, 199, 49, 176, 20, 151

Offset: 1

Author

Carmine Suriano, Sep 08 2010

Keywords

• nonn

Comments

a(n)=1 for n=A023039.

Examples

			a(4)=11 since 4^2-5*floor(4/sqrt(5))^2=16-5=11.
		

Links

• Zak Seidov, Table of n, a(n) for n = 1..1000
• Zak Seidov, Graphic of A180498.

Crossrefs

Cf. A023039, A082532.