A235386 Numbers k such that A235141(k) = 1.

1, 5, 11, 23, 33, 65, 85, 109, 133, 187, 215, 285, 361, 447, 491, 591, 643, 695, 747, 931, 991, 1193, 1267, 1343, 1569, 1739, 2087, 2181, 2277, 2471, 2573, 2669, 2781, 3327, 3557, 3681, 3923, 4299, 4431, 4561, 4833, 4969

Offset: 1

Author

Rajan Murthy, Jan 08 2014

Keywords

• nonn

Comments

The positions reflect square radii which are uniquely twice a square integer, that is, the inclusion of only one square on the y = x line.

Examples

			for n=3, a(3) = 11. The eleventh term of A235141 is 1 reflecting an increase in the square radius of the circle from exactly 8 to the open interval of (8,9).
		

Crossrefs

A000548(n) = A001481(1 + (a(n+1)-1)/2)/2.

Cf. A235141, A234300.

Formula

a(n+1) = A235142(n) + 1, a(1)=1.