%I #19 Jan 29 2020 01:37:25
%S 1,0,3,1,0,2,45,22,3,0,0,10,107,61,13,1,0,-48,20,2100,14855,9168,2390,
%T 300,15,0,0,-336,92,6320,33765,21803,6378,1010,85,3,0,11520,-2016,
%U -198296,33012,2199246,9547461,6331782,1994265,362474,39375,2394,63
%N The MC polynomials.
%C The a(n,p) polynomials, see below with the extra p for the column number, generate the coefficients of the left hand columns of triangle A163940. These polynomials are interesting in their own right. They have many curious properties; e.g., for p >= 1: a(n=1, p) = p, a(n=0, p) = 0, a(n = -1, p) = (-1)^(p+1), a(n=-2,p) = (-1)^(p+1)*(2)^(p-2) and a(n = -(2*p+1), 2*p) = 0, which is the outermost zero of the a(n, 2*p); for p >= 10: a(n=-10, p) = -362880*10^(p-10); etc.
%C The numbers in the denominators of the a(n,p) are the Minkowski numbers A053657.
%C The Maple program generates the coefficients of the polynomials that appear in the numerators of the a(n,p), see the sequence above. We have made use of a nice little program that _Peter Luschny_ recently wrote for the Minkowski numbers! For the an(p,k) in the Maple program for p >= 1 we have 0 <= k <= (2*p-2). A word of caution: The value of nmax has to be chosen sufficiently large in order to let Maple find the o.g.f.s.
%C The zero patterns of the a(n,p) polynomials resemble the Montezuma Cypress (Taxodium mucronatum). A famous Montezuma Cypress is 'El Arbol del Tule' (the Tule tree) in Mexico. It is the second stoutest tree in the world, circumference 36 meters, and is approximately 1500 years old. Considering this I propose to call the a(n,p) polynomials the MC polynomials.
%C The row sums equal n*A053657(n). [_Johannes W. Meijer_, Nov 29 2012]
%H Johannes W. Meijer, The zeros of the MC polynomials, <a href="/A163972/a163972.pdf">pdf</a> and <a href="/A163972/a163972.jpg">jpg</a>.
%e The a(n,p) formulas of the first few left hand columns of the A163940 triangle (p is the column number):
%e a(n,1) = (1)/1
%e a(n,2) = (0 + 3*n + n^2)/2
%e a(n,3) = (0 + 2*n + 45*n^2+ 22*n^3 + 3*n^4)/24
%e a(n,4) = (0 + 0*n + 10*n^2 + 107*n^3 + 61*n^4 + 13*n^5 + n^6)/48
%e a(n,5) = (0 - 48*n + 20*n^2 + 2100*n^3 + 14855*n^4 + 9168*n^5 + 2390*n^6 + 300*n^7 + 15*n^8)/5760
%e a(n,6) = (0 + 0*n -336*n^2 +92*n^3 +6320*n^4 +33765*n^5 +21803*n^6 +6378*n^7 +1010*n^8 +85*n^9 +3*n^10)/11520
%e a(n,7) = (0 + 11520*n -2016*n^2 -198296*n^3 +33012*n^4 +2199246*n^5 +9547461*n^6+ 6331782*n^7 +1994265*n^8 +362474*n^9 +39375*n^10 +2394*n^11 +63*n^12)/2903040
%p pmax:=6; nmax:=70; with(genfunc): A053657 := proc(n) local P, p, q, s, r; P := select(isprime, [$2..n]); r:=1; for p in P do s := 0: q := p-1; do if q > (n-1) then break fi; s := s + iquo(n-1, q); q := q*p; od; r := r * p^s; od; r end: for px from 1 to nmax do Gf(px):= convert(series(1/((1-(px-1)*x)^2*product((1-k*x), k=1..px-2)),x,nmax+1-px),polynom): for qy from 0 to nmax-px do a(px+qy,qy):=coeff(Gf(px),x,qy) od; od: for p from 1 to pmax do f(x):=0: for ny from p to nmax do f(x):=f(x)+a(ny,p-1)*x^(ny-p) od: f(x):= series(f(x),x, nmax): Gx:=convert(%, ratpoly): rgf_sequence('recur',Gx,x,G,n): a(n,p):=sort(simplify (rgf_expand(Gx,x,n)),n): f(p):=sort(a(n,p)*A053657(p),n,ascending): for k from 0 to 2*p-2 do an(p,k):= coeff(f(p),n,k) od; od: T:=1: for p from 1 to pmax do for k from 0 to 2*p-2 do a(T):=an(p,k): T:=T+1 od: od: seq(a(n),n=1..T-1); for p from 1 to pmax do seq(an(p,k),k=0..2*p-2) od; for p from 1 to pmax do MC(n,p):=sort(a(n,p),n,ascending) od;
%Y A000012, A000096, A163943 and A163944 are the first four left hand columns of A163940.
%Y Cf. A053657 (Minkowski), A163402 and A075264.
%K easy,sign,tabf
%O 1,3
%A _Johannes W. Meijer_, Aug 13 2009