a(n) is the total number of paths starting at (0, 0), ending at (n, 0), consisting of steps (1, 1), (1, 0), (1, -3), and staying on or above y = -1.
A379463
a(n) is the total number of paths starting at (0, 0), ending at (n, 0), consisting of steps (1, 1), (1, 0), (1, -3), and staying on or above y = -1.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =11a(6) =31a(7) =71a(8) =150a(9) =334a(10) =826a(11) =2146a(12) =5498a(13) =13690a(14) =33762a(15) =84306a(16) =214451a(17) =551107a(18) =1417291a(19) =3637627a(20) =9343555a(21) =24096675a(22) =62439587a(23) =162331747a(24) =422773098a(25) =1102422546a(26) =2879207046a(27) =7534606366a(28) =19756893196a(29) =51894005428
External references
- oeis: A379463