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A090016 Permanent of (0,1)-matrix of size n X (n+d) with d=6 and n-1 zeros not on a line. 12

%I

%S 7,49,399,3689,38087,433713,5394991,72737161,1056085191,16423175153,

%T 272275569167,4792916427369,89267526953479,1753598009244529,

%U 36232438035285807,785431570870425353,17822981129678644871

%N Permanent of (0,1)-matrix of size n X (n+d) with d=6 and n-1 zeros not on a line.

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

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

%H Indranil Ghosh, <a href="/A090016/b090016.txt">Table of n, a(n) for n = 1..444</a>

%F a(n) = (n+5)*a(n-1) + (n-2)*a(n-2), a(1)=7, a(2)=49

%F E.g.f.: 7*exp(-x)/(1-x)^8. - _Vladeta Jovovic_, Mar 19 2004

%F a(n) = (A000166(n-1)+7*A000166(n)+21*A000166(n+1)+35*A000166(n+2)+35*A000166(n+3)+21*A000166(n+4)+7*A000166(n+5)+A000166(n+6))/6!. - _Vladeta Jovovic_, Mar 19 2004

%F a(n) ~ exp(-1) * n! * n^6 / 6!. - _Vaclav Kotesovec_, Nov 30 2017

%t t={7,49};Do[AppendTo[t,(n+5)*t[[-1]]+(n-2)*t[[-2]]],{n,3,17}];t (* _Indranil Ghosh_, Feb 21 2017 *)

%Y a(n) = A090010(n-1) + A090010(n), a(1)=7

%Y Cf. A000255, A000153, A000261, A001909, A001910, A090010, A055790, A090012-A090015.

%K nonn,easy

%O 1,1

%A _Jaap Spies_, Dec 13 2003

%E Corrected by _Jaap Spies_, Jan 26 2004

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Last modified December 12 12:30 EST 2019. Contains 329958 sequences. (Running on oeis4.)