cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 10 results.

A038732 T(n,n-3), array T as in A038730.

Original entry on oeis.org

1, 8, 38, 141, 455, 1350, 3805, 10395, 27875, 73945, 194961, 512303, 1343768, 3521381, 9223435, 24152800, 63239810, 165572615, 433485350, 1134892290, 2971202146, 7778726798, 20364993198, 53316270346, 139583838315
Offset: 3

Views

Author

Clark Kimberling, May 02 2000

Keywords

Comments

First differences are essentially in A038739. - R. J. Mathar, May 23 2008

Formula

G.f.: x^3/[(1-3x+x^2)(1-x)^5].

A038733 T(n,n-4), array T as in A038730.

Original entry on oeis.org

1, 10, 57, 245, 888, 2881, 8679, 24872, 68940, 186953, 499927, 1325204, 3494249, 9184675, 24098536, 63165197, 165471668, 433350754, 1134715190, 2970971916, 7778430788, 20364616458, 53315795326, 139583244540
Offset: 4

Views

Author

Clark Kimberling, May 02 2000

Keywords

Formula

G.f.: x^4/[(1-3x+x^2)(1-x)^7].

A038734 T(n,n-5), array T as in A038730.

Original entry on oeis.org

1, 12, 80, 393, 1594, 5676, 18437, 56070, 162643, 456169, 1249622, 3368279, 8981185, 23778766, 62674883, 164736197, 432269179, 1133152915, 2968751841, 7775322683, 20360324313, 53309942401, 139575355815, 365424013769
Offset: 5

Views

Author

Clark Kimberling, May 02 2000

Keywords

Formula

G.f.: x^5/[(1-3x+x^2)(1-x)^9].

A038735 T(n,n-6), array T as in A038730.

Original entry on oeis.org

1, 14, 107, 593, 2673, 10429, 36622, 118885, 363791, 1064866, 3015563, 8334539, 22634700, 60713627, 161467437, 426957444, 1124716630, 2955628731, 7755292673, 20330279298, 53265590236, 139510843575, 365331452729
Offset: 6

Views

Author

Clark Kimberling, May 02 2000

Keywords

A026532 Ratios of successive terms are 3, 2, 3, 2, 3, 2, 3, 2, ...

Original entry on oeis.org

1, 3, 6, 18, 36, 108, 216, 648, 1296, 3888, 7776, 23328, 46656, 139968, 279936, 839808, 1679616, 5038848, 10077696, 30233088, 60466176, 181398528, 362797056, 1088391168, 2176782336, 6530347008, 13060694016, 39182082048, 78364164096, 235092492288, 470184984576
Offset: 1

Views

Author

Keywords

Comments

Preface the series with a 1: (1, 1, 3, 6, 18, 36, ...); then the next term in the series = (1, 1, 3, 6, ...) dot (1, 2, 1, 2, ...). Example: 36 = (1, 1, 3, 6, 18) dot (1, 2, 1, 2, 1) = (1 + 2 + 3 + 12 + 18). - Gary W. Adamson, Apr 18 2009
Partial products of A176059. - Reinhard Zumkeller, Apr 04 2012

Crossrefs

Cf. A038730, A038792, and A134511 for incomplete Fibonacci sequences, and A324242 for incomplete Lucas sequences.

Programs

  • Haskell
    a026532 n = a026532_list !! (n-1)
    a026532_list = scanl (*) 1 $ a176059_list
    -- Reinhard Zumkeller, Apr 04 2012
    
  • Magma
    [(1/4)*(3-(-1)^n)*6^Floor(n/2) : n in [1..30]]; // Vincenzo Librandi, Jun 08 2011
    
  • Mathematica
    FoldList[(2 + Boole[EvenQ@ #2]) #1 &, Range@ 28] (* or *)
    CoefficientList[Series[x*(1+3x)/(1-6x^2), {x,0,31}], x] (* Michael De Vlieger, Aug 02 2017 *)
    LinearRecurrence[{0,6},{1,3},30] (* Harvey P. Dale, Jul 11 2018 *)
  • PARI
    a(n)=if(n%2,3,1)*6^(n\2) \\ Charles R Greathouse IV, Jul 02 2013
    
  • Python
    def a(n): return (3 if n%2 else 1)*6**(n//2)
    print([a(n) for n in range(31)]) # Indranil Ghosh, Aug 02 2017
    
  • Sage
    [(1/2)*6^((n-2)/2)*(3*(1+(-1)^n) + sqrt(6)*(1-(-1)^n)) for n in (1..30)] # G. C. Greubel, Dec 21 2021

Formula

a(n) = T(n, 0) + T(n, 1) + ... + T(n, 2n-2), T given by A026519.
From Benoit Cloitre, Nov 14 2003: (Start)
a(n) = (1/2)*(5+(-1)^n)*a(n-1) for n>1, a(1) = 1.
a(n) = (1/4)*(3-(-1)^n)*6^floor(n/2). (End)
From Ralf Stephan, Feb 03 2004: (Start)
G.f.: x*(1+3*x)/(1-6*x^2).
a(n+2) = 6*a(n). (End)
a(n+3) = a(n+2)*a(n+1)/a(n). - Reinhard Zumkeller, Mar 04 2011
a(n) = (1/2)*6^((n-2)/2)*(3*(1+(-1)^n) + sqrt(6)*(1-(-1)^n)). - G. C. Greubel, Dec 21 2021
Sum_{n>=1} 1/a(n) = 8/5. - Amiram Eldar, Feb 13 2023

Extensions

New definition from Ralf Stephan, Dec 01 2004
Offset changed from 0 to 1 by Vincenzo Librandi, Jun 08 2011

A038792 Rectangular array defined by T(i,1) = T(1,j) = 1 for i >= 1 and j >= 1; T(i,j) = max(T(i-1,j) + T(i-1,j-1), T(i-1,j-1) + T(i,j-1)) for i >= 2, j >= 2, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 4, 5, 4, 1, 1, 5, 8, 8, 5, 1, 1, 6, 12, 13, 12, 6, 1, 1, 7, 17, 21, 21, 17, 7, 1, 1, 8, 23, 33, 34, 33, 23, 8, 1, 1, 9, 30, 50, 55, 55, 50, 30, 9, 1, 1, 10, 38, 73, 88, 89, 88, 73, 38, 10, 1, 1, 11, 47, 103, 138, 144, 144, 138, 103, 47, 11, 1
Offset: 1

Views

Author

Clark Kimberling, May 02 2000

Keywords

Comments

Antidiagonal sums: A029907.
Main diagonal: A001519 (odd-indexed Fibonacci numbers).
Next diagonal: A001906 (even-indexed Fibonacci numbers).

Examples

			From _Clark Kimberling_, Jun 20 2011: (Start)
Northwest corner begins at (i,j) = (1,1):
  1,   1,   1,   1,   1,   1,   1,   1, ...
  1,   2,   3,   4,   5,   6,   7,   8, ...
  1,   3,   5,   8,  12,  17,  23,  30, ...
  1,   4,   8,  13,  21,  33,  50,  73, ...
  1,   5,  12,  21,  34,  55,  88, 138, ...
  1,   6,  17,  33,  55,  89, 144, 232, ...
  1,   7,  23,  50,  88, 144, 233, 377, ...
(End)
Antidiagonal triangle begins as:
  1;
  1, 1;
  1, 2,  1;
  1, 3,  3,  1;
  1, 4,  5,  4,  1;
  1, 5,  8,  8,  5,  1;
  1, 6, 12, 13, 12,  6,  1;
  1, 7, 17, 21, 21, 17,  7,  1;
  1, 8, 23, 33, 34, 33, 23,  8, 1;
  1, 9, 30, 50, 55, 55, 50, 30, 9, 1;
		

Crossrefs

Main diagonal gives A001519.

Programs

  • Magma
    function t(n,k)
      if k eq 0 or n eq 0 then return 1;
      else return Max(t(n-1,k-1) + t(n-1,k), t(n-1,k-1) + t(n,k-1));
      end if; return t;
    end function;
    T:= func< n,k | t(n-k, k-1) >;
    [T(n,k): k in [1..n], n in [1..12]]; // G. C. Greubel, Apr 05 2022
    
  • Maple
    G := x*y*(1-x*y)/((x*y+x-1)*(x*y+y-1)); G := convert(series(G, x=0, 11),polynom):
    for i from 1 to 10 do series(coeff(G,x,i),y=0,11) od; # Mark van Hoeij, Nov 09 2011
    # second Maple program:
    G:= x*y*(1-x*y)/((x*y+x-1)*(x*y+y-1)):
    T:= (i, j)-> coeff(series(coeff(series(G, y, j+1), y, j), x, i+1), x, i):
    seq(seq(T(i, 1+d-i), i=1..d), d=1..12); # Alois P. Heinz, Sep 02 2019
    # third Maple program:
    T:= proc(i,j) option remember; `if`(i=1 or j=1, 1,
          max(T(i-1,j) + T(i-1,j-1), T(i-1,j-1) + T(i,j-1)))
        end:
    seq(seq(T(i, 1+d-i), i=1..d), d=1..12); # Alois P. Heinz, Sep 02 2019
  • Mathematica
    f[i_, 0]:= 1; f[0, i_]:= 1
    f[i_, j_]:= f[i,j]= Max[f[i-1,j] +f[i-1,j-1], f[i-1,j-1] +f[i,j-1]];
    T[i_, j_]:= f[i-j, j-1];
    TableForm[Table[f[i, j], {i,0,7}, {j,0,7}]]
    Table[T[i, j], {i,10}, {j,i}]//Flatten (* modified by G. C. Greubel, Apr 05 2022 *)
  • SageMath
    def t(n,k):
        if (k==0 or n==0): return 1
        else: return max(t(n-1,k-1) + t(n-1,k), t(n-1,k-1) + t(n,k-1))
    def A038792(n,k): return t(n-k, k-1)
    flatten([[A038792(n,k) for k in (1..n)] for n in (1..12)]) # G. C. Greubel, Apr 05 2022

Formula

G.f.: x*y*(1-x*y)/((x*y+x-1)*(x*y+y-1)). - Mark van Hoeij, Nov 09 2011
From Petros Hadjicostas, Sep 02 2019: (Start)
Following Dil and Mezo (2008), define the incomplete Fibonacci numbers by F(n,k) = Sum_{s = 0..k} binomial(n-1-s, s) for n >= 1 and 0 <= k <= floor((n-1)/2).
Then T(i, j) = F(i+j-1, min(i-1, j-1)) for i,j >= 1.
(End)

Extensions

New description from Benoit Cloitre, Aug 05 2003
Updated from pre-2003 triangular format to present rectangular, from Clark Kimberling, Jun 20 2011

A134511 abs(A049310) * A128174 provided both arrays are read with offset (n,k) = (0,0).

Original entry on oeis.org

1, 0, 1, 2, 0, 1, 0, 3, 0, 1, 5, 0, 4, 0, 1, 0, 8, 0, 5, 0, 1, 13, 0, 12, 0, 6, 0, 1, 0, 21, 0, 17, 0, 7, 0, 1, 34, 0, 33, 0, 23, 0, 8, 0, 1, 0, 55, 0, 50, 0, 30, 0, 9, 0, 1, 89, 0, 88, 0, 73, 0, 38, 0, 10, 0, 1, 0, 144, 0, 138, 0, 103, 0, 47, 0, 11, 0, 1, 233, 0, 232, 0, 211, 0, 141, 0, 57, 0, 12, 0, 1
Offset: 0

Views

Author

Gary W. Adamson, Oct 28 2007

Keywords

Comments

A112552(unsigned) = A128174 * A049310.
Row sums = A134512: (1, 1, 3, 4, 10, 14, 32, 46, 99, 145, ...).
From Petros Hadjicostas, Sep 03 2019: (Start)
To prove Alois P. Heinz's claim (see the Formula section and his Maple program below) we note that, for n >= 0 and 0 <= k <= n, T(n, n-k) = Sum_{r = 0 .. infinity} abs(A049310(n,r)) * A128174(r,n-k) = Sum_{r = n-k..n} abs(A049310(n,r)) * A128174(r,n-k). But A049310(n,r) = 0 when n + r is odd and A128174(r,n-k) = 1 iff r + n - k is even. Thus, when k is odd, T(n, n-k) = 0.
Assume now k is even. Then T(n, n-k) = Sum_{r = n-k..n and n+r even} abs(A049310(n,r)) = Sum_{r = n-k..n and n+r even} binomial((n+r)/2, r). Letting m = n-r (which is even), we see that the summation ranges from m = 0 to k over even numbers. Thus, let s = m/2, and so T(n, n-k) = Sum_{s = 0 .. k/2} binomial(n-s, n-2*s) = Sum_{s = 0 .. k/2} binomial(n-s, s) = F(n+1, k/2), where F(.,.) is the incomplete Fibonacci number from the references (see also the Formula section below).
(End)

Examples

			First few rows of the triangle T(n,k):
   1;
   0,  1;
   2,  0,  1;
   0,  3,  0,  1;
   5,  0,  4,  0,  1;
   0,  8,  0,  5,  0,  1;
  13,  0, 12,  0,  6,  0,  1;
   0, 21,  0, 17,  0,  7,  0,  1;
  34,  0, 33,  0, 23,  0,  8,  0,  1;
   0, 55,  0, 50,  0, 30,  0,  9,  0,  1;
  ...
		

Crossrefs

A(4n,2n) gives: A038736.

Programs

  • Maple
    N:= 20: # for the first N rows
    T128174:= Matrix(N,N,(i,j) -> `if`(j<=i, (i-j+1) mod 2, 0)):
    T049310:= Matrix(N,N):
    for i from 1 to N do
         P:= orthopoly[U](i-1,x/2);
         for j from 1 to i do
           T049310[i,j]:= abs(coeff(P,x,j-1))
         od
    od:
    A:= T049310 . T128174:
    for i from 1 to N do
    convert(A[i,1..i],list)
    od;  # Robert Israel, Mar 02 2018
    # second Maple program:
    T:= (n, k)-> `if`((n+k)::odd, 0, add(binomial(n-s, s), s=0..(n-k)/2)):
    seq(seq(T(n, k), k=0..n), n=0..12); # Alois P. Heinz, Sep 02 2019
  • Mathematica
    T[n_, k_] := If[OddQ[n+k], 0, Sum[Binomial[n-s, s], {s, 0, (n-k)/2}]];
    Table[Table[T[n, k], {k, 0, n}], {n, 0, 12}] // Flatten (* Jean-François Alcover, Dec 31 2021, after Alois P. Heinz *)

Formula

abs(A049310) * A128174 as infinite lower triangular matrices assuming both of them have offset (n,k) = (0,0).
From Petros Hadjicostas, Sep 03 2019: (Start)
Let F(m,r) = Sum_{j = 0..r} binomial(m-1-j, j) be the incomplete Fibonacci numbers from the references (defined for m >= 1 and 0 <= r <= floor((m-1)/2)).
As Alois P. Heinz observed, for n >= 0 and 0 <= k <= n, T(n, n-k) = F(n+1, k/2) when k is even, and = 0 otherwise (see his Maple program below).
(End)

Extensions

Edited by Robert Israel, Mar 02 2018

A038731 Number of columns in all directed column-convex polyominoes of area n+1.

Original entry on oeis.org

1, 3, 10, 32, 99, 299, 887, 2595, 7508, 21526, 61251, 173173, 486925, 1362627, 3797374, 10543724, 29180067, 80521055, 221610563, 608468451, 1667040776, 4558234018, 12441155715, 33900136297, 92230468249, 250570010499, 679844574322, 1842280003640
Offset: 0

Views

Author

Clark Kimberling, May 02 2000

Keywords

Comments

Apply Riordan array (1/(1-x), x/(1-x)^2) to n+1. - Paul Barry, Oct 13 2009
Binomial transform of (A001629 shifted left twice). - R. J. Mathar, Feb 06 2010

Crossrefs

Row-sums of array T as in A038730.
First differences of A030267.
Row sums of A318942(n+1).
Cf. A000045.

Programs

  • Haskell
    a038731 n = a038731_list !! n
    a038731_list = c [1] $ tail a000045_list where
       c us vs'@(v:vs) = (sum $ zipWith (*) us vs') : c (v:us) vs
    -- Reinhard Zumkeller, Oct 31 2013
  • Magma
    I:=[1, 3, 10, 32]; [n le 4 select I[n] else 6*Self(n-1)-11*Self(n-2)+6*Self(n-3)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Feb 04 2012
    
  • Mathematica
    Table[Sum[Binomial[n, k]*CoefficientList[Series[1/(1 - x - x^2)^2, {x, 0, k}], x][[-1]], {k, 0, n}], {n, 0, 27}] (* Arkadiusz Wesolowski, Feb 03 2012 *)
    LinearRecurrence[{6, -11, 6, -1}, {1, 3, 10, 32}, 30] (* Vincenzo Librandi, Feb 04 2012 *)

Formula

5*a(n) = (2n+1)*F(2n+2) - (n-4)*F(2n+1), where the F(n)'s are the Fibonacci numbers, F(0)=0, F(1)=1.
a(n) = Sum_{k=1..n+1} k*binomial(n+k-1, 2k-2). - Emeric Deutsch, Jun 11 2003
From Paul Barry, Oct 13 2009: (Start)
G.f.: (1-x)^3/(1-3x+x^2)^2.
a(n) = Sum_{k=0..n} binomial(n+k, 2k)*(k+1). (End)
a(n) = 6*a(n-1) - 11*a(n-2) + 6*a(n-3) - a(n-4). - R. J. Mathar, Feb 06 2010
a(n) = Sum_{k=0..n} (F(2k)+0^k)*F(2n-2k+1). - Paul Barry, Jun 23 2010
E.g.f.: exp(3*x/2)*(5*(5 + 4*x)*cosh(sqrt(5)*x/2) + sqrt(5)*(7 + 10*x)*sinh(sqrt(5)*x/2))/25. - Stefano Spezia, Mar 04 2025

Extensions

Entry improved by comments from Emeric Deutsch, Jun 14 2001

A137176 Hyperlucas number array T(r,n) = L(n)^(r), read by ascending antidiagonals (r >= 0, n >= 0).

Original entry on oeis.org

0, 0, 1, 0, 1, 3, 0, 1, 4, 4, 0, 1, 5, 8, 7, 0, 1, 6, 13, 15, 11, 0, 1, 7, 19, 28, 26, 18, 0, 1, 8, 26, 47, 54, 44, 29, 0, 1, 9, 34, 73, 101, 98, 73, 47, 0, 1, 10, 43, 107, 174, 199, 171, 120, 76, 0, 1, 11, 53, 150, 281, 373, 370, 291, 196, 123
Offset: 0

Views

Author

Jonathan Vos Post, Apr 04 2008

Keywords

Comments

In Theorem 17, Dil and Mezo (2008) connect the hyperlucas numbers (this array) with the incomplete Lucas numbers (A324242). - Petros Hadjicostas, Sep 03 2019

Examples

			The array T(r,n) = L(n)^(r) begins:
.....|n=0|n=1|.n=2|.n=3|.n=4.|.n=5.|..n=6.|.n=7..|..n=8..|..n=9..|.n=10..|.in.OEIS
r=0..|.0.|.1.|..3.|..4.|...7.|..11.|...18.|...29.|....47.|....76.|...123.|.A000204
r=1..|.0.|.1.|..4.|..8.|..15.|..26.|...44.|...73.|...120.|...196.|...319.|.A027961
r=2..|.0.|.1.|..5.|.13.|..28.|..54.|...98.|..171.|...291.|...487.|...806.|.A023537
r=3..|.0.|.1.|..6.|.19.|..47.|.101.|..199.|..370.|...661.|..1148.|..1954.|.A027963
r=4..|.0.|.1.|..7.|.26.|..73.|.174.|..373.|..743.|..1404.|..2552.|..4506.|.A027964
r=5..|.0.|.1.|..8.|.34.|.107.|.281.|..654.|.1397.|..2801.|..5353.|..9859.|.A053298
r=6..|.0.|.1.|..9.|.43.|.150.|.431.|.1085.|.2482.|..5283.|.10636.|.20495.|.new
r=7..|.0.|.1.|.10.|.53.|.203.|.634.|.1719.|.4201.|..9484.|.20120.|.40615.|.new
r=8..|.0.|.1.|.11.|.64.|.267.|.901.|.2620.|.6821.|.16305.|.36425.|.77040.|.new
r=9..|.0.|.1.|.12.|.76.|.343.|1244.|.3864.|10685.|.26990.|.63415.|140455.|.new
For example, T(4,5) = L(5)^(4) = L(0)^(3) + L(1)^(3) + L(2)^(3) + L(3)^(3) + L(4)^(3) + L(5)^(3) = 0 + 1 + 6 + 19 + 47 + 101 = 174. - _Petros Hadjicostas_, Sep 03 2019
		

Crossrefs

Cf. A038730, A038792, and A134511 for incomplete Fibonacci sequences, and A324242 for incomplete Lucas sequences.

Programs

  • Maple
    L:= proc(r, n) option remember; `if`(n=0, 0, `if`(r=0,
          `if`(n<3, 2*n-1, L(0, n-2)+L(0, n-1)), L(r-1, n)+L(r, n-1)))
        end:
    seq(seq(L(d-n, n), n=0..d), d=0..12);  # Alois P. Heinz, Sep 03 2019
  • Mathematica
    L[r_, n_] := L[r, n] = If[n == 0, 0, If[r == 0, If[n < 3, 2n-1, L[0, n-2] + L[0, n-1]], L[r-1, n] + L[r, n-1]]];
    Table[L[d-n, n], {d, 0, 12}, {n, 0, d}] // Flatten (* Jean-François Alcover, Sep 26 2019, from Maple *)

Formula

T(r,n) = L(n)^(r) = Apply partial sum operator r times to Lucas numbers A000204.
From Petros Hadjicostas, Sep 03 2019: (Start)
T(r, n) = L(n)^(r) = Sum_{k = 0..n} L(k)^(r-1) for r >= 1, with T(0,n) = L(n)^(0) = L(n) = A000204(n), T(r,0) = L(0)^(r) = 0, and T(r,1) = L(1)^(r) = 1. (See Definition 13 in Dil and Mezo (2008).)
G.f. for row r: Sum_{n >= 0} L(n)^(r)*t^n = t * (1+2*t)/((1-t-t^2) * (1-t)^r). (Corrected from Proposition 14 in Dil and Mezo (2008).)
(End)

A324242 Incomplete Lucas numbers: irregular triangular array L(n,k) = Sum_{j = 0..k} (n/(n-j)) * binomial(n-j, j), read by rows, with n >= 1 and 0 <= k <= floor(n/2).

Original entry on oeis.org

1, 1, 3, 1, 4, 1, 5, 7, 1, 6, 11, 1, 7, 16, 18, 1, 8, 22, 29, 1, 9, 29, 45, 47, 1, 10, 37, 67, 76, 1, 11, 46, 96, 121, 123, 1, 12, 56, 133, 188, 199, 1, 13, 67, 179, 284, 320, 322, 1, 14, 79, 235, 417, 508, 521, 1, 15, 92, 302, 596, 792, 841, 843, 1, 16, 106, 381, 831, 1209, 1349, 1364
Offset: 1

Views

Author

Petros Hadjicostas, Sep 02 2019

Keywords

Comments

For additional properties of the incomplete Lucas numbers and special cases not listed here, see Filipponi (1996, pp. 45-53).

Examples

			Triangle L(n,k) (with rows n >= 1 and columns k >= 0) begins as follows:
  1;
  1,  3;
  1,  4;
  1,  5,  7;
  1,  6, 11;
  1,  7, 16,  18;
  1,  8, 22,  29;
  1,  9, 29,  45,  47;
  1, 10, 37,  67,  76;
  1, 11, 46,  96, 121, 123;
  1, 12, 56, 133, 188, 199;
  ...
Row sums are 1, 4, 5, 13, 18, 42, 60, 131, 191, 398, 589, 1186, 1775, 3482, 5257, 10103, 15360, ...
		

Crossrefs

Cf. A038730, A038792, and A134511 for various versions of the incomplete Fibonacci numbers.

Programs

  • Mathematica
    Flatten[Table[Sum[(n/(n-j))*Binomial[n-j, j],{j,0,k}],{n,1,15},{k,0,Floor[n/2]}]] (* Stefano Spezia, Sep 03 2019 *)

Formula

L(n,k) = F(n-1, k-1) + F(n+1, k) for n >= 1 and 0 <= k <= floor(n/2), where F(n,k) = Sum_{j = 0..k} binomial(n-1-j, j) are the incomplete Fibonacci numbers (defined for n >= 1 and 0 <= k <= floor((n-1)/2)).
L(n+2, k+1) = L(n+1, k+1) + L(n,k) for n >= 1 and 0 <= k <= floor((n-1)/2).
L(n,k) = F(n+2,k) - F(n-2, k-2) for n >= 3 and 2 <= k <= floor((n+1)/2).
Special cases: L(n,0) = 1 (n >= 1), L(n,1) = n+1 (n >= 2), L(n,2) = (n^2-n+2)/2 = A000124(n-1) (n >= 4), and L(n, floor(n/2)) = A000204(n) (n >= 1).
Sum of row n = (3 + (-1)^n)*A000204(n)/4 + n*A000045(n)/2.
G.f. for column k >= 1: t^(2*k)*((A000204(2*k) + t*A000204(2*k-1))*(1-t)^(k+1) - t^2*(2-t))/((1-t)^(k+1) * (1-t-t^2)).
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