Triangular array read by rows: The sum of squares of the number of common points in all pairs of lattice paths from (0,0) to (x,y), for 0 <= y <= x (the unnormalized second moment).
A306687
Triangular array read by rows: The sum of squares of the number of common points in all pairs of lattice paths from (0,0) to (x,y), for 0 <= y <= x (the unnormalized second moment).
Terms
- a(0) =1a(1) =4a(2) =26a(3) =9a(4) =92a(5) =474a(6) =16a(7) =240a(8) =1704a(9) =8084a(10) =25a(11) =520a(12) =4879a(13) =29560a(14) =134450a(15) =36a(16) =994a(17) =11928a(18) =89928a(19) =498140a(20) =2208612a(21) =49a(22) =1736a(23) =25956a(24) =238440a(25) =1580810a(26) =8265432a(27) =36024884a(28) =64a(29) =2832
External references
- oeis: A306687