Number of isoscent sequences of length n with exactly two descents.
A243475
Number of isoscent sequences of length n with exactly two descents.
Terms
- a(0) =2a(1) =28a(2) =241a(3) =1667a(4) =10142a(5) =56748a(6) =299485a(7) =1514445a(8) =7415873a(9) =35424718a(10) =165963977a(11) =765639729a(12) =3488740303a(13) =15739196772a(14) =70434524941a(15) =313136541466
External references
- oeis: A243475