Coefficient of q^1 in nu(n), where nu(0)=1, nu(1)=b and, for n>=2, nu(n)=b*nu(n-1)+lambda*(1+q+q^2+...+q^(n-2))*nu(n-2) with (b,lambda)=(1,2).

A074352

Coefficient of q^1 in nu(n), where nu(0)=1, nu(1)=b and, for n>=2, nu(n)=b*nu(n-1)+lambda*(1+q+q^2+...+q^(n-2))*nu(n-2) with (b,lambda)=(1,2).

Terms

    a(0) =0a(1) =0a(2) =0a(3) =2a(4) =8a(5) =22a(6) =60a(7) =146a(8) =352a(9) =814a(10) =1860a(11) =4170a(12) =9256a(13) =20326a(14) =44300a(15) =95874a(16) =206320a(17) =441758a(18) =941780a(19) =2000058a(20) =4233144a(21) =8932310a(22) =18796700a(23) =39457522a(24) =82643328a(25) =172743182a(26) =360399460a(27) =750625066a(28) =1560902472a(29) =3241109574

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