A025574 - OEIS

%I #12 Sep 08 2019 00:53:47

%S 1,10,61,356,2058,11892,68860,399828,2328066,13591364,79538750,

%T 466489520,2741310614,16137748980,95152639095,561856988100,

%U 3322001296650,19664909435556,116535288360106,691284470658376,4104450497833036,24390520567203960,145053186645586383

%N T(2n,n+1), where T is the array defined in A025564.

%C Coefficient of y^(n+1) in (y^2+2*y+1)*(y^2+y+1)^(2*n-2). - _Robert Israel_, Sep 07 2019

%H Robert Israel, <a href="/A025574/b025574.txt">Table of n, a(n) for n = 1..1278</a>

%p f:= n -> coeff((y^2+2*y+1)*(y^2+y+1)^(2*n-2),y,n+1);

%p map(f, [$1..30]); # _Robert Israel_, Sep 07 2019

%Y Cf. A025564.

%K nonn

%O 1,2

%A _Clark Kimberling_

%E More terms from _Sean A. Irvine_, Sep 07 2019