[go: up one dir, main page]
More Web Proxy on the site http://driver.im/
login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Alternating row sums of triangle A049029 (S2(5)).
0

%I #8 Jul 27 2017 04:25:58

%S 1,4,31,359,5546,107249,2492701,67693534,2103854581,73651161959,

%T 2868077514776,122980857764819,5758029769553101,292305762924889804,

%U 15992593021331060611,938143525674896325299,58739433900424758545186,3910020681156059085488189

%N Alternating row sums of triangle A049029 (S2(5)).

%F a(n) = Sum_{m=1..n} (-1)^(m+1)*A049029(n,m), n>=1.

%F E.g.f.: (from Jabotinsky structure): 1-exp(1-1/(1-4*x)^(1/4)).

%F a(n) = y(n), where y(0) = -1, y(1) = 1, y(2) = 4, y(3) = 31, y(4) = 359, and -32*k*(1 + k)*(1 + 2 k)*(1 + 4 k)*(3 + 4 k)*y(k) + (1679 + 5920 k + 8080 k^2 + 5120 k^3 + 1280 k^4)*y(k+1) + (-2550 - 4580 k - 2880 k^2 - 640 k^3)*y(k+2) + (675 + 640 k + 160 k^2)*y(k+3) + (-50 - 20 k)*y(k+4) + y(k+5) = 0. - _Benedict W. J. Irwin_, Jul 12 2017

%t Table[DifferenceRoot[Function[{y, k}, {-32 k (1 + k) (1 + 2 k) (1 + 4 k) (3 + 4 k) y[k] + (1679 + 5920 k + 8080 k^2 + 5120 k^3 + 1280 k^4) y[1 + k] + (-2550 - 4580 k - 2880 k^2 - 640 k^3) y[2 + k] + (675 + 640 k + 160 k^2) y[3 + k] + (-50 - 20 k) y[4 + k] + y[5 + k] == 0, y[0] == -1, y[1] == 1, y[2] == 4, y[3] == 31, y[4] == 359}]][n], {n, 1, 20}] (* _Benedict W. J. Irwin_, Jul 12 2017 *)

%Y Cf. A049120 (row sums).

%K nonn,easy

%O 1,2

%A _Wolfdieter Lang_, Oct 17 2008