a(0) = 1, a(n+1) = 3 * a(n) - F(n)*(F(n) + 1), where F(n) = A000045(n) is n-th Fibonacci number.

A011769

a(0) = 1, a(n+1) = 3 * a(n) - F(n)*(F(n) + 1), where F(n) = A000045(n) is n-th Fibonacci number.

Terms

    a(0) =1a(1) =3a(2) =7a(3) =19a(4) =51a(5) =141a(6) =393a(7) =1107a(8) =3139a(9) =8955a(10) =25675a(11) =73945a(12) =213825a(13) =620595a(14) =1807263a(15) =5279283a(16) =15465139a(17) =45420261a(18) =133708777a(19) =394446691a(20) =1165855131a(21) =3451793403a(22) =10235554347a(23) =30392965809a(24) =90357645121a(25) =268922897571a(26) =801139867063

External references