A256449 - OEIS

%I #13 Mar 30 2015 21:41:22

%S 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,

%T -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,

%U -15,2,5,14,-4,11,-24,13,0,4,-9,-8,-10,6,-2,0,-2,16,11,-7,-13,7,-11,0

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

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

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

%H Antti Karttunen, <a href="/A256449/b256449.txt">Table of n, a(n) for n = 1..564</a>

%H A. Karttunen, <a href="http://oeis.org/plot2a?name1=A256449&amp;name2=A251723&amp;tform1=untransformed&amp;tform2=untransformed&amp;shift=0&amp;radiop1=matp&amp;drawlines=true">Sequences A256449 and A251723 compared with OEIS Plot2-script</a> (See also the ratio-plots linked in A256447.)

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

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

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

%o (Scheme)

%o (define (A256449 n) (- (A256447 n) (A256448 n)))

%o (define (A256449 n) (- (* 2 (A250477 n)) (A250474 n) (A250474 (+ n 1))))

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

%K sign

%O 1,1

%A _Antti Karttunen_, Mar 29 2015