Define an array as follows: b(i,0)=b(0,j)=1, b(i,j) = 2*b(i-1,j-1) + b(i-1,j) + b(i,j-1). Then a(n) = b(n,n).
A069835
Define an array as follows: b(i,0)=b(0,j)=1, b(i,j) = 2*b(i-1,j-1) + b(i-1,j) + b(i,j-1). Then a(n) = b(n,n).
Terms
- a(0) =1a(1) =4a(2) =22a(3) =136a(4) =886a(5) =5944a(6) =40636a(7) =281488a(8) =1968934a(9) =13875544a(10) =98365972a(11) =700701808a(12) =5011371964a(13) =35961808432a(14) =258805997752
External references
- oeis: A069835