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Row sums of triangle in A139040.
1

%I #6 Jun 12 2017 06:58:32

%S 1,2,3,4,6,8,11,14,18,22,28,34,43,52,65,78,97,116,144,172,213,254,314,

%T 374,462,550,679,808,997,1186,1463,1740,2146,2552,3147,3742,4614,5486,

%U 6764,8042,9915,11788,14533,17278,21301,25324,31220,37116,45757

%N Row sums of triangle in A139040.

%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,-1,0,0,1,-1).

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

%F a(n) = a(n-1) + a(n-2) - a(n-3) + a(n-6) - a(n-7), a(0) = 1, a(1) = 2, a(2) = 3, a(3) = 4, a(4) = 6, a(5) = 8, a(6) = 11.

%t LinearRecurrence[{1,1,-1,0,0,1,-1},{1,2,3,4,6,8,11},60] (* _Harvey P. Dale_, Jun 12 2017 *)

%Y Cf. A139040

%K easy,nonn

%O 0,2

%A _Philippe Deléham_, Feb 25 2014