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%I #10 Mar 30 2012 17:34:16
%S 2,5,9,12,15,19,22,26,29,32,36,39,42,46,49,53,56,59,63,66,70,73,76,80,
%T 83,86,90,93,97,100,103,107,110,114,117,120,124,127,130,134,137,141,
%U 144,147,151,154,157,161,164,168,171,174,178,181,185,188,191,195,198,201
%N a(n)=a(n-1) +A108173(n+1) -A108173(n).
%C Tribonacci version of A001950 using beta, the positive real root of x^3-x^2-x-1, as the constant.
%t NSolve[x^3 - x^2 - x - 1 = 0, x] beta = 1.8392867552141612 a[n_] = 1 + Ceiling[(n - 1)*beta^2] (* A007066-like*) aa = Table[a[n], {n, 1, 100}] (*A076662-like*) b = Table[a[n] - a[n - 1], {n, 2, Length[aa]}] F[1] = 2; F[n_] := F[n] = F[n - 1] + b[[n]] (* A000195-like*) c = Table[F[n], {n, 1, Length[b] - 1}]
%Y Cf. A007066, A076662, A001950.
%K nonn
%O 1,1
%A _Roger L. Bagula_, Jun 13 2005
%E Partially edited by _N. J. A. Sloane_, May 04 2007
%E Correction of definition and offset by R. J. Mathar, Mar 12 2012
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