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A090015 Permanent of (0,1)-matrix of size n X (n+d) with d=5 and n-1 zeros not on a line. 3
6, 36, 258, 2136, 19998, 208524, 2393754, 29976192, 406446774, 5930064372, 92608986546, 1541044428456, 27216454135758, 508388707585116, 10013199347882058, 207381428863832784, 4505207996358719334 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

Brualdi, Richard A. and Ryser, Herbert J., Combinatorial Matrix Theory, Cambridge NY (1991), Chapter 7.

LINKS

Indranil Ghosh, Table of n, a(n) for n = 1..445

Seok-Zun Song et al., Extremes of permanents of (0,1)-matrices, Lin. Algebra and its Applic. 373 (2003), pp. 197-210.

FORMULA

a(n) = (n+4)*a(n-1) + (n-2)*a(n-2), a(1)=6, a(2)=36

a(n) ~ exp(-1) * n! * n^5 / 5!. - Vaclav Kotesovec, Nov 30 2017

a(n) = ((n^6+21*n^5+160*n^4+545*n^3+814*n^2+415*n+1)*exp(-1)*Gamma(n, -1)+(-1)^n*(n^5+20*n^4+141*n^3+422*n^2+499*n+154))/120. - Robert Israel, Nov 26 2018

MAPLE

f:= gfun:-rectoproc({a(n) = (n+4)*a(n-1) + (n-2)*a(n-2), a(1)=6, a(2)=36}, a(n), remember):

map(f, [$1..40]); # Robert Israel, Nov 26 2018

MATHEMATICA

t={6, 36}; Do[AppendTo[t, (n+4)*t[[-1]]+(n-2)*t[[-2]]], {n, 3, 17}]; t (* Indranil Ghosh, Feb 21 2017 *)

CROSSREFS

a(n) = A001910(n-1) + A001910(n), a(1)=6

Cf. A000255, A000153, A000261, A001909, A001910, A090010, A055790, A090012-A090016.

Sequence in context: A049428 A129063 A221461 * A299330 A335811 A144892

Adjacent sequences:  A090012 A090013 A090014 * A090016 A090017 A090018

KEYWORD

nonn,easy

AUTHOR

Jaap Spies, Dec 13 2003

EXTENSIONS

Corrected by Jaap Spies, Jan 26 2004

STATUS

approved

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Last modified June 21 01:04 EDT 2021. Contains 345330 sequences. (Running on oeis4.)