A061886 Largest square less than or equal to sum of previous terms.

1, 1, 1, 1, 4, 4, 9, 16, 36, 64, 121, 256, 484, 961, 1936, 3844, 7569, 15129, 30276, 60516, 121104, 242064, 483025, 966289, 1932100, 3865156, 7728400, 15452761, 30902481, 61811044, 123609924, 247212729, 494439696, 988850916, 1977669841

Offset: 0

Author

Henry Bottomley, May 12 2001

Keywords

• nonn

Examples

			a(6) = 9 since 1+1+1+1+4+4 = 12 and 9 is the largest square less than or equal to this.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A061883.

Programs

Haskell

a061886 n = a061886_list !! n
a061886_list = 1 : zipWith (-) (tail a060984_list) a060984_list
-- Reinhard Zumkeller, Dec 24 2013

Formula

For n > 0: a(n) = A060984(n+1)-A060984(n) = A048760(A060984(n)).

Extensions

Formula corrected by Reinhard Zumkeller, Dec 24 2013