This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A090014 Permanent of (0,1)-matrix of size n X (n+d) with d=4 and n-1 zeros not on a line. 2

%I

%S 5,25,155,1135,9545,90445,952175,11016595,138864365,1893369505,

%T 27756952355,435287980375,7269934161905,128812336516885,

%U 2413131201408695,47652865538001595,989254278781162325

%N Permanent of (0,1)-matrix of size n X (n+d) with d=4 and n-1 zeros not on a line.

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

%H Indranil Ghosh, <a href="/A090014/b090014.txt">Table of n, a(n) for n = 1..445</a>

%H Seok-Zun Song et al., <a href="http://dx.doi.org/10.1016/S0024-3795(03)00382-3">Extremes of permanents of (0,1)-matrices</a>, Lin. Algebra and its Applic. 373 (2003), pp. 197-210.

%F a(n) = (n+3)*a(n-1) + (n-2)*a(n-2), a(1)=5, a(2)=25.

%F a(n) ~ exp(-1) * n! * n^4 / 24. - _Vaclav Kotesovec_, Nov 30 2017

%t f[x_] := x*HypergeometricPFQ[{1, 5}, {}, x/(x+1)]/(x+1); Total /@ Partition[ CoefficientList[ Series[f[x], {x, 0, 18}], x], 2, 1] // Rest (* _Jean-François Alcover_, Nov 12 2013, after A001909 and _Mark van Hoeij_ *)

%t t={5,25};Do[AppendTo[t,(n+3)*t[[-1]]+(n-2)*t[[-2]]],{n,3,17}];t (* _Indranil Ghosh_, Feb 21 2017 *)

%Y a(n) = A001909(n-1) + A001909(n), a(1)=5

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

%K nonn,easy

%O 1,1

%A _Jaap Spies_, Dec 13 2003

%E Corrected by _Jaap Spies_, Jan 26 2004

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 7 20:33 EST 2019. Contains 329849 sequences. (Running on oeis4.)