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 1-3 of 3 results.

A378064 a(n) = 5*n^4 - 6*n^2 + 1. Column 4 of A378066.

Original entry on oeis.org

1, 0, 57, 352, 1185, 2976, 6265, 11712, 20097, 32320, 49401, 72480, 102817, 141792, 190905, 251776, 326145, 415872, 522937, 649440, 797601, 969760, 1168377, 1396032, 1655425, 1949376, 2280825, 2652832, 3068577, 3531360, 4044601, 4611840, 5236737, 5923072
Offset: 0

Views

Author

Peter Luschny, Nov 17 2024

Keywords

Crossrefs

Cf. A378066.

Programs

  • Maple
    seq(5*n^4 - 6*n^2 + 1, n = 0..33);
  • Python
    def A378064(n): return (m:=n**2)*(5*m-6)+1 # Chai Wah Wu, Nov 18 2024

Formula

a(n) = [x^n] (-57*x^3 - 67*x^2 + 5*x - 1)/(x - 1)^5.

A378063 a(n) = (-2*n)^n * Euler(n, (n - 1)/(2*n)) for n >= 1, and a(0) = 1. Main diagonal of A378066.

Original entry on oeis.org

1, 1, -3, -26, 1185, 15376, -2749355, -49816976, 22790134017, 533858404096, -498990299504499, -14365294449638912, 23891962452055766497, 816609772823716089856, -2201371244223771530940315, -87139486416935710159898624, 355987789164484245477279893505
Offset: 0

Views

Author

Peter Luschny, Nov 17 2024

Keywords

Crossrefs

Cf. A378066.

Programs

  • Maple
    a := n -> ifelse(n = 0, 1, (-2*n)^n * euler(n, (n - 1)/(2*n))):
    seq(a(n), n = 0..16);

Formula

a(n) = Sum_{j=0..n} binomial(n, j)*Euler(j)*(-n)^j.

A378065 a(n) = (-10)^n * Euler(n, 2/5). Row 5 of A378066.

Original entry on oeis.org

1, 1, -24, -74, 2976, 15376, -906624, -6563024, 514546176, 4789470976, -469222938624, -5338232282624, 627559296638976, 8437702651826176, -1157248322241921024, -17953287144063002624, 2814090582404042981376, 49478116534660975230976, -8724885890905288434253824
Offset: 0

Views

Author

Peter Luschny, Nov 17 2024

Keywords

Crossrefs

Cf. A378066.

Programs

  • Maple
    a := n -> (-10)^n * euler(n, 2/5): seq(a(n), n = 0..18);
    # Or:
    ser := series(exp(x)/cosh(5*x), x, 20):
    seq(n!*coeff(ser, x, n), n = 0..18);

Formula

a(n) = n! * [x^n] exp(x)/cosh(5*x).
a(n) = Sum_{j=0..n} (-5)^j*binomial(n, j)*Euler(j).
Showing 1-3 of 3 results.