A055082 Number of 4 X n binary matrices with no zero rows or columns, up to row and column permutation.

1, 8, 42, 179, 633, 2001, 5745, 15274, 38000, 89331, 199715, 427184, 878152, 1741964, 3345562, 6239390, 11327863, 20065972, 34747460, 58924066, 98002370, 160086580, 257148244, 406637336, 633669040, 973971441, 1477810227, 2215179768, 3282598034, 4811946882

Offset

1,2

Links

Andrew Howroyd, Table of n, a(n) for n = 1..1000

F. Harary, L. March and R. W. Robinson, On enumerating certain design problems in terms of bicolored graphs with no isolates, Environment and Planning, B 5 (1978), 31-43.

F. Harary, L. March and R. W. Robinson, On enumerating certain design problems in terms of bicolored graphs with no isolates, Environment and Planning B: Urban Analytics and City Science, 5 (1978), 31-43. [Annotated scanned copy]

Prog

(PARI) Vec((G(4, x) - G(3, x))*(1 - x) + O(x^30)) \\ G defined in A028657. - Andrew Howroyd, Feb 28 2023

Crossrefs

Column k=4 of A056152.

Cf. A024206, A055609, A054976, A048291.

Sequence in context: A287221 A119965 A229729 * A266940 A212337 A289031

Adjacent sequences: A055079 A055080 A055081 * A055083 A055084 A055085

Keyword

nonn

Author

Vladeta Jovovic, Jun 13 2000

Extensions

Terms a(21) and beyond from Andrew Howroyd, Mar 25 2020

Status

approved