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%I #15 Oct 25 2017 06:01:33
%S 2,28,182,864,3474,12660,43358,142552,455930,1430796,4431078,13595664,
%T 41441570,125732836,380212142,1147057800,3454803594,10393245180,
%U 31240551350,93849578560,281817169202,846013542228,2539215029502,7620094559544,22865383949594
%N Third diagonal of triangle in A046740.
%H D. P. Roselle, <a href="http://dx.doi.org/10.1090/S0002-9939-1968-0218256-9">Permutations by number of rises and successions</a>, Proc. Amer. Math. Soc., 19 (1968), 8-16.
%H D. P. Roselle, <a href="/A046739/a046739.pdf"> Permutations by number of rises and successions</a>, Proc. Amer. Math. Soc., 19 (1968), 8-16. [Annotated scanned copy]
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (10,-40,82,-91,52,-12).
%F a(n) = 3^n-(3*n+1)*2^(n-1)+2*n^2-2*n+1. - _Vladeta Jovovic_, Jan 04 2003
%F G.f.: -2*x^4*(9*x^2-4*x-1) / ((x-1)^3*(2*x-1)^2*(3*x-1)). [_Colin Barker_, Feb 03 2013]
%o (PARI) a(n) = 3^n-(3*n+1)*2^(n-1)+2*n^2-2*n+1; \\ _Michel Marcus_, Oct 25 2017
%Y Cf. A046740.
%K nonn,easy
%O 4,1
%A _N. J. A. Sloane_, May 15 2002
%E More terms from _Colin Barker_, Feb 03 2013
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