Number of slanted 3 X n (i=1..3) X (j=i..n+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, and 4 in the lower right corner.
A165386
Number of slanted 3 X n (i=1..3) X (j=i..n+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, and 4 in the lower right corner.
Terms
- a(0) =3a(1) =40a(2) =305a(3) =1622a(4) =6868a(5) =25036a(6) =82224a(7) =250208a(8) =718536a(9) =1972132a(10) =5220384a(11) =13417184a(12) =33652952a(13) =82699012a(14) =199729888a(15) =475260768a(16) =1116459752a(17) =2593550148a(18) =5965976992a(19) =13605076608a(20) =30787314104a(21) =69191005796a(22) =154539160288a(23) =343241755840
External references
- oeis: A165386