A350111 Triangle read by rows: T(n,k) is the number of tilings of an (n+k)-board using k (1,3)-fences and n-k squares.
1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 2, 3, 4, 2, 0, 1, 3, 6, 7, 4, 0, 0, 1, 4, 9, 12, 8, 0, 0, 0, 1, 5, 13, 20, 16, 8, 4, 2, 1, 1, 6, 18, 32, 36, 28, 19, 12, 3, 0, 1, 7, 24, 50, 69, 69, 58, 31, 9, 0, 0, 1, 8, 31, 74, 120, 144, 127, 78, 27, 0, 0, 0
Offset: 0
Examples
Triangle begins: 1; 1, 0; 1, 0, 0; 1, 0, 0, 0; 1, 1, 1, 1, 1; 1, 2, 3, 4, 2, 0; 1, 3, 6, 7, 4, 0, 0; 1, 4, 9, 12, 8, 0, 0, 0; 1, 5, 13, 20, 16, 8, 4, 2, 1; 1, 6, 18, 32, 36, 28, 19, 12, 3, 0; 1, 7, 24, 50, 69, 69, 58, 31, 9, 0, 0; 1, 8, 31, 74, 120, 144, 127, 78, 27, 0, 0, 0; 1, 9, 39, 105, 195, 264, 265, 189, 81, 27, 9, 3, 1; 1, 10, 48, 144, 300, 458, 522, 432, 270, 132, 58, 24, 4, 0;
Links
- Michael A. Allen, On a Two-Parameter Family of Generalizations of Pascal's Triangle, arXiv:2209.01377 [math.CO], 2022.
- Michael A. Allen, On A Two-Parameter Family of Generalizations of Pascal's Triangle, J. Int. Seq. 25 (2022) Article 22.9.8.
- Michael A. Allen and Kenneth Edwards, On Two Families of Generalizations of Pascal's Triangle, J. Int. Seq. 25 (2022) Article 22.7.1.
Crossrefs
Programs
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Mathematica
f[n_]:=If[n<0,0,f[n-1]+x*f[n-2]+KroneckerDelta[n,0]]; T[n_, k_]:=Module[{j=Floor[(n+k)/4],r=Mod[n+k,4]}, Coefficient[f[j]^(4-r)*f[j+1]^r,x,k]]; Flatten@Table[T[n,k], {n, 0, 13}, {k, 0, n}] (* or *) T[n_,k_]:=If[k<0 || n
Formula
T(n,k) = T(n-1,k) + T(n-2,k-1) - T(n-3,k-1) + T(n-3,k-2) + T(n-4,k-1) + T(n-4,k-3) + 2*T(n-4,k-4) + T(n-5,k-2) + 2*T(n-5,k-3) - T(n-5,k-4) - T(n-6,k-3)-T(n-6,k-5) - T(n-7,k-4)-T(n-7,k-5) - T(n-7,k-6) - T(n-8,k-7)-T(n-8,k-8) + delta(n,0)*delta(k,0) - delta(n,2)*delta(k,1) - delta(n,3)*delta(k,2) - delta(n,4)*delta(k,4) with T(n
T(n,0) = 1.
T(n,n) = delta(n mod 4,0).
T(n,1) = n-3 for n>2.
T(4*j-r,4*j-p) = 0 for j>0, p=1,2,3, and r=1,...,p.
T(4*(j-1)+p,4*(j-1)) = T(4*j,4*j-p) = j^p for j>0 and p=0,1,2,3,4.
T(4*j+1,4*j-1) = 4*j(j+1)/2 for j>0.
T(4*j+2,4*j-2) = 4*C(j+2,4) + 6*C(j+1,2)^2 for j>1.
G.f. of row sums: (1-x-x^3)/((1-2*x)*(1-x^2)*(1+2*x^2+x^3+x^4)).
G.f. of antidiagonal sums: (1-x^2-x^3+x^4-x^6)/((1-x-x^2)*(1-x^4)*(1+3*x^4+x^8)).
T(n,k) = T(n-1,k) + T(n-1,k-1) for n>=3*k+1 if k>=0.
A350112 Triangle read by rows: T(n,k) is the number of tilings of an (n+k)-board using k (1,4)-fences and n-k squares.
1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 2, 0, 1, 3, 6, 10, 9, 4, 0, 0, 1, 4, 10, 16, 16, 8, 0, 0, 0, 1, 5, 14, 25, 28, 16, 0, 0, 0, 0, 1, 6, 19, 38, 48, 32, 16, 8, 4, 2, 1, 1, 7, 25, 56, 80, 80, 60, 40, 25, 15, 3, 0, 1, 8, 32, 80, 136, 166, 157, 128, 95, 40, 9, 0, 0
Offset: 0
Comments
This is the m=5 member in the sequence of triangles A007318, A059259, A350110, A350111, A350112 which give the number of tilings of an (n+k) X 1 board using k (1,m-1)-fences and n-k unit square tiles. A (1,g)-fence is composed of two unit square tiles separated by a gap of width g.
It is also the m=5, t=2 member of a two-parameter family of triangles such that T(n,k) is the number of tilings of an (n+(t-1)*k) X 1 board using k (1,m-1;t)-combs and n-k unit square tiles. A (1,g;t)-comb is composed of a line of t unit square tiles separated from each other by gaps of width g.
T(5*j+r-k,k) is the coefficient of x^k in (f(j,x))^(5-r)*(f(j+1,x))^r for r=0,1,2,3,4 where f(n,x) is one form of a Fibonacci polynomial defined by f(n+1,x)=f(n,x)+x*f(n-1,x) where f(0,x)=1 and f(n<0,x)=0.
T(n+5-k,k) is the number of subsets of {1,2,...,n} of size k such that no two elements in a subset differ by 5.
Sum of (5j+r)-th antidiagonal (counting initial 1 as the 0th) is f(j)^(5-r)*f(j+1)^r where j=0,1,..., r=0,1,2,3,4, and f(n) is the Fibonacci number A000045(n+1).
Examples
Triangle begins: 1; 1, 0; 1, 0, 0; 1, 0, 0, 0; 1, 0, 0, 0, 0; 1, 1, 1, 1, 1, 1; 1, 2, 3, 4, 5, 2, 0; 1, 3, 6, 10, 9, 4, 0, 0; 1, 4, 10, 16, 16, 8, 0, 0, 0; 1, 5, 14, 25, 28, 16, 0, 0, 0, 0; 1, 6, 19, 38, 48, 32, 16, 8, 4, 2, 1; 1, 7, 25, 56, 80, 80, 60, 40, 25, 15, 3, 0; 1, 8, 32, 80, 136, 166, 157, 128, 95, 40, 9, 0, 0; 1, 9, 40, 112, 217, 309, 346, 330, 223, 105, 27, 0, 0, 0;
Links
- Michael A. Allen, On a Two-Parameter Family of Generalizations of Pascal's Triangle, arXiv:2209.01377 [math.CO], 2022.
- Michael A. Allen, On A Two-Parameter Family of Generalizations of Pascal's Triangle, J. Int. Seq. 25 (2022) Article 22.9.8.
- Michael A. Allen and Kenneth Edwards, On Two Families of Generalizations of Pascal's Triangle, J. Int. Seq. 25 (2022) Article 22.7.1.
Crossrefs
Programs
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Mathematica
f[n_]:=If[n<0,0,f[n-1]+x*f[n-2]+KroneckerDelta[n,0]]; T[n_, k_]:=Module[{j=Floor[(n+k)/5], r=Mod[n+k,5]}, Coefficient[f[j]^(5-r)*f[j+1]^r,x,k]]; Flatten@Table[T[n,k], {n, 0, 13}, {k, 0, n}]
Formula
T(n,0) = 1.
T(n,n) = delta(n mod 5,0).
T(n,1) = n-4 for n>3.
T(5*j-r,5*j-p) = 0 for j>0, p=1,2,3,4, and r=1,...,p.
T(5*(j-1)+p,5*(j-1)) = T(5*j,5*j-p) = j^p for j>0 and p=0,1,...,5.
T(5*j+1,5*j-1) = 5*j(j+1)/2 for j>0.
T(5*j+2,5*j-2) = 5*C(j+2,4) + 10*C(j+1,2)^2 for j>1.
T(n,k) = T(n-1,k) + T(n-1,k-1) for n >= 4*k+1 if k >= 0.
A354665
Triangle read by rows, T(n,k) = T(n-1,k) + T(n-1,k-1) - T(n-2,k-1) + T(n-2,k-2) + T(n-3,k-1) - T(n-3,k-3) + delta(n,0)*delta(k,0) - delta(n,1)*delta(k,1), T(n
1, 1, 0, 1, 0, 1, 1, 1, 2, 0, 1, 2, 4, 0, 1, 1, 3, 6, 3, 3, 0, 1, 4, 9, 8, 9, 0, 1, 1, 5, 13, 17, 18, 6, 4, 0, 1, 6, 18, 30, 36, 20, 16, 0, 1, 1, 7, 24, 48, 66, 55, 40, 10, 5, 0, 1, 8, 31, 72, 114, 120, 100, 40, 25, 0, 1, 1, 9, 39, 103, 186
Offset: 0
Comments
This is the m=2, t=3 member of a two-parameter family of triangles such that T(n,k) is the number of tilings of an (n+(t-1)*k) X 1 board using k (1,m-1;t)-combs and n-k unit square tiles. A (1,g;t)-comb is composed of a line of t unit square tiles separated from each other by gaps of width g.
T(2*j+r-2*k,k) is the coefficient of x^k in (f(j,x))^(2-r)*(f(j+1,x))^r for r=0,1, where f(n,x) is a Narayana's cows polynomial defined by f(n,x)=f(n-1,x)+x*f(n-3,x)+delta(n,0) where f(n<0,x)=0.
T(n+4-2*k,k) is the number of subsets of {1,2,...,n} of size k such that no two elements in a subset differ by 2 or 4.
Examples
Triangle begins: 1; 1, 0; 1, 0, 1; 1, 1, 2, 0; 1, 2, 4, 0, 1; 1, 3, 6, 3, 3, 0; 1, 4, 9, 8, 9, 0, 1; 1, 5, 13, 17, 18, 6, 4, 0; 1, 6, 18, 30, 36, 20, 16, 0, 1; 1, 7, 24, 48, 66, 55, 40, 10, 5, 0; 1, 8, 31, 72, 114, 120, 100, 40, 25, 0, 1; 1, 9, 39, 103, 186, 234, 221, 135, 75, 15, 6, 0; ...
Links
- Michael A. Allen, On a Two-Parameter Family of Generalizations of Pascal's Triangle, arXiv:2209.01377 [math.CO], 2022.
- Michael A. Allen, On A Two-Parameter Family of Generalizations of Pascal's Triangle, J. Int. Seq. 25 (2022) Article 22.9.8.
Crossrefs
Programs
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Mathematica
T[n_, k_]:=If[k<0 || n
Formula
T(n,0) = 1.
T(n,n) = delta(n mod 2,0).
T(n,1) = n-2 for n>1.
T(2*j-r,2*j-1) = 0 for j>0, r=0,1.
T(2*(j-1)+p,2*(j-1)) = j^p for j>0 and p=0,1,2.
T(2*(j-1)+3,2*(j-1)) = j^2*(j+1)/2 for j>0.
T(2*j+p,2*j-p) = C(j+1,2)^p for j>0 and p=0,1,2.
G.f. of row sums: (1-x)/(1-2*x).
G.f. of sums of T(n-2*k,k) over k: (1-x^3)/((1-x-x^3)*(1+x^4-x^6)).
T(n,k) = T(n-1,k) + T(n-1,k-1) for n>=2*k+1 if k>=0.
A354666
Triangle read by rows, T(n,k) = T(n-1,k) + T(n-2,k-1) + 2*T(n-2,k-2) - T(n-3,k-1) - T(n-3,k-2) + T(n-4,k-1) + T(n-4,k-2) - T(n-4,k-3) - T(n-4,k-4) + delta(n,0)*delta(k,0) - delta(n,2)*(delta(k,1) + delta(k,2)), T(n
1, 1, 0, 1, 0, 1, 1, 0, 2, 0, 1, 1, 4, 0, 1, 1, 2, 6, 0, 3, 0, 1, 3, 9, 4, 9, 0, 1, 1, 4, 12, 10, 18, 0, 4, 0, 1, 5, 16, 21, 36, 10, 16, 0, 1, 1, 6, 21, 36, 60, 30, 40, 0, 5, 0, 1, 7, 27, 57, 100, 81, 100, 20, 25, 0, 1, 1, 8, 34, 84, 158, 168
Offset: 0
Comments
This is the m=2, t=4 member of a two-parameter family of triangles such that T(n,k) is the number of tilings of an (n+(t-1)*k) X 1 board using k (1,m-1;t)-combs and n-k unit square tiles. A (1,g;t)-comb is composed of a line of t unit square tiles separated from each other by gaps of width g.
T(2*j+r-3*k,k) is the coefficient of x^k in (f(j,x))^(2-r)*(f(j+1,x))^r for r=0,1, where f(n,x) is a (1,4)-bonacci polynomial defined by f(n,x)=f(n-1,x)+x*f(n-4,x)+delta(n,0) where f(n<0,x)=0.
T(n+6-3*k,k) is the number of subsets of {1,2,...,n} of size k such that no two elements in a subset differ by 2, 4, or 6.
Examples
Triangle begins: 1; 1, 0; 1, 0, 1; 1, 0, 2, 0; 1, 1, 4, 0, 1; 1, 2, 6, 0, 3, 0; 1, 3, 9, 4, 9, 0, 1; 1, 4, 12, 10, 18, 0, 4, 0; 1, 5, 16, 21, 36, 10, 16, 0, 1; 1, 6, 21, 36, 60, 30, 40, 0, 5, 0; 1, 7, 27, 57, 100, 81, 100, 20, 25, 0, 1; 1, 8, 34, 84, 158, 168, 200, 70, 75, 0, 6, 0; 1, 9, 42, 118, 243, 322, 400, 231, 225, 35, 36, 0, 1; ...
Links
- Michael A. Allen, On a Two-Parameter Family of Generalizations of Pascal's Triangle, arXiv:2209.01377 [math.CO], 2022.
- Michael A. Allen, On A Two-Parameter Family of Generalizations of Pascal's Triangle, J. Int. Seq. 25 (2022) Article 22.9.8.
Crossrefs
Programs
-
Mathematica
T[n_,k_]:=If[k<0 || n
Formula
T(n,0) = 1.
T(n,n) = delta(n mod 2,0).
T(n,1) = n-3 for n>2.
T(2*j-r,2*j-1) = 0 for j>0, r=-1,0,1.
T(2*(j-1)+p,2*(j-1)) = j^p for j>0 and p=0,1,2.
T(2*j+p,2*(j-1)) = j^2*((j+1)/2)^p for j>0 and p=1,2.
T(2*j+3,2*(j-1)) = (j*(j+1))^2*(j+2)/12 for j>0.
T(2*(j+p),2*j-p) = C(j+2,3)^p for j>0 and p=0,1,2.
G.f. of row sums: (1-2*x^2)/(1-x-3*x^2+2*x^3).
G.f. of sums of T(n-3*k,k) over k: (1-x^5-x^8)/(1-x-x^5+x^6-x^7-2*x^8+x^9-x^10+x^13+x^16).
T(n,k) = T(n-1,k) + T(n-1,k-1) for n>=3*k+1 if k>=0.
A354667 Triangle read by rows: T(n,k) is the number of tilings of an (n+4*k) X 1 board using k (1,1;5)-combs and n-k squares.
1, 1, 0, 1, 0, 1, 1, 0, 2, 0, 1, 0, 4, 0, 1, 1, 1, 6, 0, 3, 0, 1, 2, 9, 0, 9, 0, 1, 1, 3, 12, 5, 18, 0, 4, 0, 1, 4, 16, 12, 36, 0, 16, 0, 1, 1, 5, 20, 25, 60, 15, 40, 0, 5, 0, 1, 6, 25, 42, 100, 42, 100, 0, 25, 0, 1, 1, 7, 31, 66, 150, 112, 200
Offset: 0
Comments
This is the m=2, t=5 member of a two-parameter family of triangles such that T(n,k) is the number of tilings of an (n+(t-1)*k) X 1 board using k (1,m-1;t)-combs and n-k unit square tiles. A (1,g;t)-comb is composed of a line of t unit square tiles separated from each other by gaps of width g.
T(2*j+r-4*k,k) is the coefficient of x^k in (f(j,x))^(2-r)*(f(j+1,x))^r for r=0,1, where f(n,x) is a (1,5)-bonacci polynomial defined by f(n,x)=f(n-1,x)+x*f(n-5,x)+delta(n,0) where f(n<0,x)=0.
T(n+8-4*k,k) is the number of subsets of {1,2,...,n} of size k such that no two elements in a subset differ by 2, 4, 6, or 8.
Examples
Triangle begins: 1; 1, 0; 1, 0, 1; 1, 0, 2, 0; 1, 0, 4, 0, 1; 1, 1, 6, 0, 3, 0; 1, 2, 9, 0, 9, 0, 1; 1, 3, 12, 5, 18, 0, 4, 0; 1, 4, 16, 12, 36, 0, 16, 0, 1; 1, 5, 20, 25, 60, 15, 40, 0, 5, 0; 1, 6, 25, 42, 100, 42, 100, 0, 25, 0, 1; 1, 7, 31, 66, 150, 112, 200, 35, 75, 0, 6, 0; ...
Links
- Michael A. Allen, On a Two-Parameter Family of Generalizations of Pascal's Triangle, arXiv:2209.01377 [math.CO], 2022.
- Michael A. Allen, On A Two-Parameter Family of Generalizations of Pascal's Triangle, J. Int. Seq. 25 (2022) Article 22.9.8.
Crossrefs
Programs
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Mathematica
T[n_,k_]:=If[k<0 || n
Formula
T(n,k) = T(n-1,k) + T(n-1,k-1) - T(n-2,k-1) + 2*T(n-2,k-2) + T(n-3,k-1) - T(n-3,k-2) - 2*T(n-3,k-3) - T(n-4,k-1) + T(n-4,k-2) + T(n-4,k-3) - T(n-4,k-4) + T(n-5,k-1) - 2*T(n-5,k-3) + T(n-5,k-5) + delta(n,0)*delta(k,0) - delta(n,1)*delta(k,1) - delta(n,2)*delta(k,2) - delta(n,3)*(delta(k,1) - delta(k,3)) with T(n,k<0) = T(n
T(n,0) = 1.
T(n,n) = delta(n mod 2,0).
T(n,1) = n-4 for n>3.
T(2*j+r,2*j-1) = 0 for j>0, r=-1,0,1,2.
T(n,2*j) = C(n/2,j)^2 for j>0 and n even and 2*j <= n <= 2*j+8.
T(n,2*j) = C((n-1)/2,j)*C((n+1)/2,j) for j>0 and n odd and 2*j < n < 2*j+8.
T(2*j+3*p,2*j-p) = C(j+3,4)^p for j>0 and p=0,1,2.
G.f. of row sums: (1-x-x^2)/(1-2*x-x^2+2*x^3).
G.f. of sums of T(n-4*k,k) over k: (1-x^5-x^7-x^10+x^15)/(1-x-x^5+x^6-x^7+x^8-x^9-2*x^10+x^11-x^12+2*x^15-x^16+2*x^17+x^20-x^25).
T(n,k) = T(n-1,k) + T(n-1,k-1) for n>=4*k+1 if k>=0.
A354668 Triangle read by rows: T(n,k) is the number of tilings of an (n+2*k) X 1 board using k (1,2;3)-combs and n-k squares.
1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 2, 0, 1, 1, 3, 4, 0, 0, 1, 2, 5, 8, 0, 0, 1, 1, 3, 8, 12, 0, 3, 3, 0, 1, 4, 12, 18, 9, 12, 9, 0, 0, 1, 5, 16, 27, 25, 29, 27, 0, 0, 1, 1, 6, 21, 42, 51, 66, 54, 0, 6, 4, 0, 1, 7, 27, 62, 95, 135, 108, 36
Offset: 0
Comments
This is the m=3, t=3 member of a two-parameter family of triangles such that T(n,k) is the number of tilings of an (n+(t-1)*k) X 1 board using k (1,m-1;t)-combs and n-k unit square tiles. A (1,g;t)-comb is composed of a line of t unit square tiles separated from each other by gaps of width g.
T(3*j+r-2*k,k) is the coefficient of x^k in (f(j,x))^(3-r)*(f(j+1,x))^r for r=0,1, where f(n,x) is a Narayana's cows polynomial defined by f(n,x)=f(n-1,x)+x*f(n-3,x)+delta(n,0) where f(n<0,x)=0.
T(n+6-2*k,k) is the number of subsets of {1,2,...,n} of size k such that no two elements in a subset differ by 3 or 6.
Examples
Triangle begins: 1; 1, 0; 1, 0, 0; 1, 0, 0, 1; 1, 0, 1, 2, 0; 1, 1, 3, 4, 0, 0; 1, 2, 5, 8, 0, 0, 1; 1, 3, 8, 12, 0, 3, 3, 0; 1, 4, 12, 18, 9, 12, 9, 0, 0; 1, 5, 16, 27, 25, 29, 27, 0, 0, 1; 1, 6, 21, 42, 51, 66, 54, 0, 6, 4, 0; 1, 7, 27, 62, 95, 135, 108, 36, 30, 16, 0, 0; ...
Links
- Michael A. Allen, On a Two-Parameter Family of Generalizations of Pascal's Triangle, arXiv:2209.01377 [math.CO], 2022.
- Michael A. Allen, On A Two-Parameter Family of Generalizations of Pascal's Triangle, J. Int. Seq. 25 (2022) Article 22.9.8.
Crossrefs
Programs
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Mathematica
f[n_]:=If[n<0, 0, f[n-1]+x*f[n-3]+KroneckerDelta[n,0]]; T[n_, k_]:=Module[{j=Floor[(n+2*k)/3], r=Mod[n+2*k,3]}, Coefficient[f[j]^(3-r)*f[j+1]^r, x, k]]; Flatten@Table[T[n,k], {n, 0, 11}, {k, 0, n}]
Formula
T(n,0) = 1.
T(n,n) = delta(n mod 3,0).
T(n,1) = n-4 for n>3.
T(3*j-r,3*j-p) = 0 for j>0, p=1,2, and r=1-p,...,p.
T(n,2*j) = C(n/2,j)^2 for j>0 and n even and 2*j <= n <= 2*j+8.
T(n,2*j) = C((n-1)/2,j)*C((n+1)/2,j) for j>0 and n odd and 2*j < n < 2*j+8.
T(2*j+3*p,2*j-p) = C(j+3,4)^p for j>0 and p=0,1,2.
G.f. of sums of T(n-2*k,k) over k: (1+x^3-x^4-x^5+x^6-2*x^7-x^8-x^9-2*x^10-x^12-x^13-x^15)/((1-x)*(1+x+x^2)*(1-x-x^3)*(1+3*x^3+7*x^6+9*x^9+7*x^12+3*x^15+x^18)).
T(n,k) = T(n-1,k) + T(n-1,k-1) for n>=4*k+1 if k>=0.
Comments