A256449 a(n) = A256447(n) - A256448(n).

3, 2, 1, 0, 2, -3, 2, 0, 0, 3, 0, 1, 5, 3, -1, -3, 3, -1, -1, 3, 1, 0, -7, -10, 4, 5, 0, -1, -1, -31, -2, 0, -2, -14, -3, 1, -5, 5, 9, 0, 7, 7, 6, 5, 4, -6, -22, 5, 9, 7, -9, -1, -3, -6, 9, -15, 2, 5, 14, -4, 11, -24, 13, 0, 4, -9, -8, -10, 6, -2, 0, -2, 16, 11, -7, -13, 7, -11, 0

Offset: 1

Author

Antti Karttunen, Mar 29 2015

Keywords

• sign

Comments

Positions of zeros: 4, 8, 9, 11, 22, 27, 32, 40, 64, 71, 79, 104, 113, 126, 140, 201, 225, 332, 333, 394, 451, ...

Corresponding primes: 7, 19, 23, 31, 79, 103, 131, 173, 311, 353, 401, 569, 617, 701, 809, 1229, 1427, 2237, 2239, 2707, 3187, ...

Links

• Antti Karttunen, Table of n, a(n) for n = 1..564
• A. Karttunen, Sequences A256449 and A251723 compared with OEIS Plot2-script (See also the ratio-plots linked in A256447.)

Crossrefs

Cf. A250474, A250477, A251723, A256446, A256447, A256448, A256470.

Programs

Scheme

(define (A256449 n) (- (A256447 n) (A256448 n)))
(define (A256449 n) (- (* 2 (A250477 n)) (A250474 n) (A250474 (+ n 1))))

Formula

a(n) = A256447(n) - A256448(n).

a(n) = 2*A250477(n) - A250474(n) - A250474(n+1).

a(n) = 3 - A256470(n).