A251551 a(n) = A251546(n) - A251549(n).

-1, 1, -1, 1, 1, 1, 1, 1, -1, 3, 3, 3, 3, 3, -1, 7, 7, 7, 7, 7, 7, 5, 1, 1, 1, 1, 1, 1, 1, -1, 5, 5, 11, 11, 11, 11, 11, 11, 19, 19, 21, 21, 17, 17, 17, 17, 17, 23, 23, 23, 17, 17, 17, 17, 17, 25, 25, 25, 25, 25, 23, 17

Offset: 1

Author

N. J. A. Sloane, Dec 18 2014

Keywords

• sign

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A098550, A247253, A251416, A251417, A251546-A251552.

Programs

Haskell

a251551 n = a251546 n - a251549 n  -- Reinhard Zumkeller, Dec 19 2014