A185178 - OEIS

A185178

Number of different values of the permanent of an n X n (0,1)-matrix with exactly three 1's in each row and each column.

1, 1, 2, 4, 8, 18

(list; graph; refs; listen; history; text; internal format)

OFFSET

3,3

COMMENTS

The values a(n) are unknown for n>=9.

REFERENCES

V. I. Bolshakov, On spectrum of permanent on Lambda_n^k, Proc. of Seminar on Discrete Math. and Appl., Moscow State Univ. (1986), 65-73 (in Russian).

LINKS

V. S. Shevelev, Some problems of the theory of enumerating the permutations with restricted position, Journal of Soviet Mathematics, 61 (4) (1992) 2272-2317 (see pp. 2307-2309).

CROSSREFS

Cf. A185177 (values of the permanent), A176211, A176212.

KEYWORD

nonn,bref,hard,more

AUTHOR

STATUS

approved