login
3-wave sequence beginning with 2's.
0

%I #8 Dec 15 2017 17:35:00

%S 2,2,2,4,6,10,12,22,28,50,62,112,140,252,314,566,706,1272,1586,2858,

%T 3564,6422,8008,14430,17994,32424,40432,72856,90850,163706,204138,

%U 367844,458694,826538,1030676,1857214,2315908,4173122,5203798,9376920

%N 3-wave sequence beginning with 2's.

%C The 3-wave sequence with initial values a, b, c is formed by the following construction:

%C a.......a+b+c............3a+5b+6c...

%C ..b...b+c...a+2b+2c..2a+4b+5c...

%C ....c..........a+2b+3c...

%C Dropping middle row gives A052994.

%H F. v. Lamoen, <a href="http://home.wxs.nl/~lamoen/wiskunde/wave.htm">Wave sequences</a>

%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (0,2,0,1,0,-1).

%F G.f.: (-2x^2+2x+2)/(x^6-x^4-2x^2+1).

%F a(n) = 2*A038196(n).

%Y Cf. A038196, A052994 (bisection)

%K easy,nonn

%O 0,1

%A _Jason Earls_, Apr 30 2001

%E More terms from Larry Reeves (larryr(AT)acm.org), May 10 2001