Triangle T(m,k) read by rows, where T(m,k) is the number of ways in which 1 <= k <= m positions can be picked in an m X m square array such that their adjacency graph consists of a single component. Two positions (s,t), (u,v) are considered as adjacent if max(abs(s-u), abs(t-v)) <= 1.

A098485

Triangle T(m,k) read by rows, where T(m,k) is the number of ways in which 1 <= k <= m positions can be picked in an m X m square array such that their adjacency graph consists of a single component. Two positions (s,t), (u,v) are considered as adjacent if max(abs(s-u), abs(t-v)) <= 1.

Terms

    a(0) =1a(1) =4a(2) =6a(3) =9a(4) =20a(5) =48a(6) =16a(7) =42a(8) =132a(9) =419a(10) =25a(11) =72a(12) =256a(13) =973a(14) =3682a(15) =36a(16) =110a(17) =420a(18) =1747a(19) =7484a(20) =31992a(21) =49a(22) =156a(23) =624a(24) =2741a(25) =12562a(26) =58620a(27) =273556a(28) =64a(29) =210

External references