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.

A079341 Triangular array read by rows: GCDs of entries in A010940.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 24, 12, 8, 6, 24, 4, 24, 3, 8, 24, 24, 4, 276, 92, 138, 276, 92, 276, 69, 92, 276, 276, 92, 2024, 506, 2024, 1012, 2024, 253, 2024, 2024, 184, 92, 10626, 10626, 3542, 1518, 759, 506, 1518, 966, 322, 42504, 7084, 6072, 759, 2024
Offset: 0

Views

Author

Jon Perry, Jan 04 2003

Keywords

Links

Crossrefs

Cf. A010940, A079342.

Programs

  • PARI
    y=(1-x)^24; for (m=0,12, for (n=m,12,print1(gcd(polcoeff(y,m),polcoeff(y,n))",")))

Extensions

Base sequence name changed by Michel Marcus and Georg Fischer, Aug 24 2020

A078490 Sorted A079341.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 4, 4, 6, 8, 8, 12, 24, 24, 24, 24, 24, 69, 92, 92, 92, 92, 92, 138, 184, 253, 276, 276, 276, 276, 276, 322, 506, 506, 644, 759, 759, 966, 1012, 1518, 1518, 1748, 2024, 2024, 2024, 2024, 2024, 2024, 3542, 3864, 4807, 6072, 6072
Offset: 0

Views

Author

Jon Perry, Jan 04 2003

Keywords

Links

Crossrefs

Cf. A010940, A079341.

Programs

  • PARI
    v=vector(100); vc=1; y=(1-x)^24; for (m=0,12, for (n=m,12,v[vc]=gcd(polcoeff(y,m),polcoeff(y,n)); vc++)); vecsort(vecextract(v,concat("1..",vc-1)))

A078488 First differences of coefficients of g.f. (1-x)^24.

Original entry on oeis.org

-25, 300, -2300, 12650, -53130, 177100, -480700, 1081575, -2042975, 3268760, -4457400, 5200300, -5200300, 4457400, -3268760, 2042975, -1081575, 480700, -177100, 53130, -12650, 2300, -300, 25
Offset: 1

Views

Author

Jon Perry, Jan 04 2003

Keywords

Crossrefs

Cf. A010940, A010941.

Programs

  • Mathematica
    Differences@ CoefficientList[Series[(1 - x)^24, {x, 0, 24}], x] (* Michael De Vlieger, Aug 24 2020 *)
  • PARI
    y=(1-x)^24; for (n=1,24,print1(polcoeff(y,n)-polcoeff(y,n-1)","))

Formula

a(n) = (-1)^n * binomial(25,n). - Georg Fischer, Aug 24 2020

Extensions

Definition corrected by Michel Marcus and Georg Fischer, Aug 24 2020
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.