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 1-7 of 7 results.

A102055 Column 1 of A102054, the matrix inverse of A060083 (Euler polynomials).

Original entry on oeis.org

1, 2, 1, 4, -13, 142, -1931, 36296, -893273, 27927346, -1081725559, 50861556172, -2854289486309, 188475382997654, -14467150771771043, 1277417937676246672, -128570745743431055281, 14632875988040732946106, -1869882665740777942166543, 266593648798424693540514836
Offset: 0

Views

Author

Paul D. Hanna, Dec 28 2004

Keywords

Comments

1-a(n+1) equals the n-th partial sum of the Genocchi numbers (A001469).

Crossrefs

Programs

  • PARI
    {a(n)=local(M=matrix(n+2,n+2));M[1,1]=1;if(n>0,M[2,1]=1;M[2,2]=1); for(r=3,n+2, for(c=1,r,M[r,c]=if(c==1,M[r-1,1], if(c==r,1,M[r,c]=M[r-1,c]-((matrix(r-1,r-1,i,j,M[i,j]))^-1)[r-1,c-1])))); return(if(n==0,1,M[n+2,2]))}

Formula

a(n) = 1 - Sum_{k=1, n} A001469(k) for n>0, with a(0)=1.
This sequence's twin numbers are given in A133135. - Paul Curtz, Aug 07 2008

A102054 Triangular matrix, read by rows, where T(n,k) = T(n-1,k) - [T^-1](n-1,k-1); also equals the matrix inverse of A060083 (Euler polynomials).

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 4, -2, 4, 1, 1, -13, 26, -10, 5, 1, 1, 142, -229, 116, -25, 6, 1, 1, -1931, 3181, -1567, 371, -49, 7, 1, 1, 36296, -59700, 29464, -6922, 952, -84, 8, 1, 1, -893273, 1469380, -725108, 170398, -23358, 2100, -132, 9, 1, 1, 27927346, -45938639, 22669816, -5327198, 730252, -65526, 4152
Offset: 0

Views

Author

Paul D. Hanna, Dec 28 2004

Keywords

Comments

Column 1 forms A102055. Column 2 forms A102056.

Examples

			T(5,3) = -10 = T(4,3) - A060083(4,2) = 4 - 14.
T(6,2) = -229 = T(5,2) - A060083(5,1) = 26 - 255.
Rows begin:
[1],
[1,1],
[1,2,1],
[1,1,3,1],
[1,4,-2,4,1],
[1,-13,26,-10,5,1],
[1,142,-229,116,-25,6,1],
[1,-1931,3181,-1567,371,-49,7,1],
[1,36296,-59700,29464,-6922,952,-84,8,1],...
The matrix inverse is equal to A060083:
[1],
[ -1,1],
[1,-2,1],
[ -3,5,-3,1],
[17,-28,14,-4,1],
[ -155,255,-126,30,-5,1],...
		

Crossrefs

Programs

  • PARI
    {T(n,k)=local(M=matrix(n+1,n+1));M[1,1]=1;if(n>0,M[2,1]=1;M[2,2]=1); for(r=3,n+1, for(c=1,r,M[r,c]=if(c==1,M[r-1,1], if(c==r,1,M[r,c]=M[r-1,c]-((matrix(r-1,r-1,i,j,M[i,j]))^-1)[r-1,c-1])))); return(M[n+1,k+1])}

Formula

T(n, k) = T(n-1, k) - A060083(n-1, k-1), for n>0, with T(0, 0)=1.

A102056 Column 2 of A102054, the matrix inverse of A060083 (Euler polynomials).

Original entry on oeis.org

1, 3, -2, 26, -229, 3181, -59700, 1469380, -45938639, 1779367231, -83663906454, 4695118012798, -310029578255977, 23797509154723361, -2101268283286737704, 211490399673452191176, -24070116208693613274035, 3075833697885980827017235, -438528974913900528707713514
Offset: 0

Views

Author

Paul D. Hanna, Dec 28 2004

Keywords

Crossrefs

Programs

  • PARI
    
    				

A004172 Triangle of coefficients of Euler polynomials E_2n(x) (exponents in increasing order).

Original entry on oeis.org

1, 0, -1, 1, 0, 1, 0, -2, 1, 0, -3, 0, 5, 0, -3, 1, 0, 17, 0, -28, 0, 14, 0, -4, 1, 0, -155, 0, 255, 0, -126, 0, 30, 0, -5, 1, 0, 2073, 0, -3410, 0, 1683, 0, -396, 0, 55, 0, -6, 1, 0, -38227, 0, 62881, 0, -31031, 0, 7293, 0, -1001, 0, 91, 0, -7, 1, 0, 929569, 0
Offset: 0

Views

Author

Keywords

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 809.

Crossrefs

Cf. A060083.

Programs

  • Mathematica
    Flatten[Table[CoefficientList[EulerE[2n, x], x], {n, 0, 8}]] (* Jean-François Alcover, Jul 21 2011 *)

A060082 Coefficients of even-indexed Euler polynomials (falling powers without zeros).

Original entry on oeis.org

1, 1, -1, 1, -2, 1, 1, -3, 5, -3, 1, -4, 14, -28, 17, 1, -5, 30, -126, 255, -155, 1, -6, 55, -396, 1683, -3410, 2073, 1, -7, 91, -1001, 7293, -31031, 62881, -38227, 1, -8, 140, -2184, 24310, -177320, 754572, -1529080, 929569, 1, -9, 204, -4284, 67626, -753610, 5497596, -23394924, 47408019
Offset: 0

Views

Author

Wolfdieter Lang, Mar 29 2001

Keywords

Comments

E(2n,x) = x^(2n) + Sum_{k=1..n} a(n,k)*x^(2n-2k+1).

Examples

			E(0,x) = 1.
E(2,x) = x^2 - x.
E(4,x) = x^4 - 2*x^3 + x.
E(6,x) = x^6 - 3*x^5 + 5*x^3 - 3*x.
E(8,x) = x^8 - 4*x^7 + 14*x^5 - 28*x^3 + 17*x.
E(10,x) = x^10 - 5*x^9 + 30*x^7 - 126*x^5 + 255*x^3 - 155*x.
		

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 809.

Crossrefs

E(2n, 1/2)*(-4)^n = A000364(n) (signless Euler numbers without zeros).
-E(2n, -1/2)*(-4)^n/3 = A076552(n), -E(2n, 1/3)*(-9)^n/2 = A002114(n).
Cf. A060083 (rising powers), A060096-7 (Euler polynomials), A004172 (with zeros).
Columns (left edge) include A000330, A053132. Columns (right edge) include A001469.

Programs

  • Mathematica
    Table[ CoefficientList[ EulerE[2*n, x], x] // Reverse // DeleteCases[#, 0]&, {n, 0, 9}] // Flatten (* Jean-François Alcover, Jun 21 2013 *)
  • PARI
    {B(n,v='x)=sum(i=0,n,binomial(n,i)*bernfrac(i)*v^(n-i))} E(n,v='x)=2/(n+1)*(B(n+1,v)-2^(n+1)*B(n+1,v/2)) \\ Ralf Stephan, Nov 05 2004

Formula

E(n, x) = 2/(n+1) * [B(n+1, x) - 2^(n+1)*B(n+1, x/2) ], with B(n, x) the Bernoulli polynomials.

Extensions

Edited by Ralf Stephan, Nov 05 2004

A141684 Triangle read by rows formed from Euler polynomials: p(x,n) = if(n mod 2 = 1, 2^(1 + ((n - 1)/2))*EulerE(n, x), EulerE(n, x)); t(n,m) = Coefficients(p(x,n)).

Original entry on oeis.org

1, -1, 2, 0, -1, 1, 1, 0, -6, 4, 0, 1, 0, -2, 1, -4, 0, 20, 0, -20, 8, 0, -3, 0, 5, 0, -3, 1, 34, 0, -168, 0, 140, 0, -56, 16, 0, 17, 0, -28, 0, 14, 0, -4, 1, -496, 0, 2448, 0, -2016, 0, 672, 0, -144, 32, 0, -155, 0, 255, 0, -126, 0, 30, 0, -5, 1
Offset: 1

Views

Author

Roger L. Bagula and Gary W. Adamson, Sep 08 2008

Keywords

Comments

Row sums are {1, 1, 0, -1, 0, 4, 0, -34, 0, 496, 0, ...}.

Examples

			{   1},
{  -1,    2},
{   0,   -1,    1},
{   1,    0,   -6,   4},
{   0,    1,    0,  -2,     1},
{  -4,    0,   20,   0,   -20,    8},
{   0,   -3,    0,   5,     0,   -3,   1},
{  34,    0, -168,   0,   140,    0, -56, 16},
{   0,   17,    0, -28,     0,   14,   0, -4,    1},
{-496,    0, 2448,   0, -2016,    0, 672,  0, -144, 32},
{   0, -155,    0, 255,     0, -126,   0, 30,    0, -5, 1}
		

Crossrefs

Cf. A060083, A004172, etc.

Programs

  • Mathematica
    T[x_, n_] := If[Mod[n, 2] == 1, 2^(1 + ((n - 1)/2))*EulerE[n, x], EulerE[n, x]]; Table[Expand[T[x, n]], {n, 0, 10}]; Table[CoefficientList[T[x, n], x], {n, 0, 10}]; Flatten[%]

Extensions

Edited by N. J. A. Sloane, Jan 06 2009

A171683 Triangle T(n,k) which contains 4*n!*2^floor((n+1)/2) times the coefficient [t^n x^k] exp(t*x)/(3 + exp(2*t)) in row n, column k.

Original entry on oeis.org

1, -1, 2, -1, -2, 2, 1, -6, -6, 4, 10, 4, -12, -8, 4, 26, 100, 20, -40, -20, 8, -154, 156, 300, 40, -60, -24, 8, -1646, -2156, 1092, 1400, 140, -168, -56, 16, 1000, -13168, -8624, 2912, 2800, 224, -224, -64, 16, 92744, 18000, -118512, -51744, 13104, 10080, 672, -576, -144, 32
Offset: 0

Views

Author

Roger L. Bagula, Dec 15 2009

Keywords

Comments

The bivariate Taylor expansion of exp(t*x)/(3+exp(2*t)) is 1/4 + (x/4-1/8)*t +(-1/16+x^2/8-x/8)*t^2+...
Row n contains the coefficients of [x^k] of the polynomial in front of t^n, multiplied by 4*floor((n+1)/2)*n!.
Row sums are: 1, 1, -1, -7, -2, 94, 266, -1378, -15128, -36344, 839144,...

Examples

			The triangle starts in row n=0, columns 0<=k <=n as
      1;
     -1,      2;
     -1,     -2,       2;
      1,     -6,      -6,      4;
     10,      4,     -12,     -8,     4;
     26,    100,      20,    -40,   -20,     8;
   -154,    156,     300,     40,   -60,   -24,    8;
  -1646,  -2156,    1092,   1400,   140,  -168,  -56,   16;
   1000, -13168,   -8624,   2912,  2800,   224, -224,  -64,   16;
  92744,  18000, -118512, -51744, 13104, 10080,  672, -576, -144, 32;
  ...
		

Crossrefs

Programs

  • Mathematica
    Clear[p, g, m, a];
    m = 1;
    p[t_] = 2^(m + 1)*Exp[t*x]/(-1 + 2^(m + 1) + Exp[2^m*t]) Table[ FullSimplify[ExpandAll[2^ Floor[(n + 1)/2]*n!*SeriesCoefficient[ Series[p[t], {t, 0, 30}], n]]], {n, 0, 10}]
    a = Table[CoefficientList[FullSimplify[ExpandAll[2^Floor[(n + 1)/2]*n!*SeriesCoefficient[ Series[p[t], {t, 0, 30}], n]]], x], {n, 0, 10}]
    Flatten[a]

Extensions

Number of variables in use reduced from 4 to 2, keyword:tabl added - The Assoc. Eds. of the OEIS, Oct 20 2010
Showing 1-7 of 7 results.