%I #30 Jan 22 2022 23:36:18
%S 2,4,-2,6,-3,9,-7,12,-9,14,-12,16,-13,19,-17,21,-18,24,-22,26,-23,29,
%T -27,32,-29,34,-32,36,-33,39,-37,42,-39,44,-42,46,-43,49,-47,52,-49,
%U 54,-52,56,-53,59,-57,61,-58,64,-62,66,-63,69,-67,72,-69,74,-72,76
%N First differences of A328190.
%C Conjecture from _N. J. A. Sloane_, Nov 05 2019: (Start)
%C a(4t) = 5t+1(+1 if binary expansion of t ends in odd number of 0's) for t >= 1,
%C a(4t+1) = -(5t-2(+1 if binary expansion of t ends in odd number of 0's)) for t >= 1,
%C a(4t+2) = 5t+4 for t >= 0,
%C a(4t+3) = -(5t+2) for t >= 0.
%C These formulas explain all the known terms.
%C a(2t) is closely related to A298468. The expressions for a(4t) and a(4t+1) can also be written in terms of A328979.
%C The conjecture would establish that the terms lie on two straight lines, of slopes +-5/4.
%C There is a similar conjecture for A328190. (End)
%H Peter Kagey, <a href="/A328196/b328196.txt">Table of n, a(n) for n = 1..10000</a>
%Y Cf. A298468, A328190, A328979.
%Y The negative terms are (conjecturally) listed in A329982 (see also A328983).
%Y See A328984 and A328985 for simpler sequences which almost have the properties of A329190 and A328196. - _N. J. A. Sloane_, Nov 07 2019
%K sign
%O 1,1
%A _Peter Kagey_, Oct 07 2019