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 1-2 of 2 results.

A238955 Maximal level size of arcs in divisor lattice in graded colexicographic order.

Original entry on oeis.org

0, 1, 1, 2, 1, 3, 6, 1, 3, 4, 7, 12, 1, 3, 5, 8, 11, 18, 30, 1, 3, 5, 6, 8, 12, 15, 19, 24, 38, 60, 1, 3, 5, 7, 8, 13, 16, 19, 20, 30, 37, 46, 58, 90, 140, 1, 3, 5, 7, 8, 8, 13, 17, 20, 23, 20, 31, 36, 43, 52, 47, 66, 80, 100, 122, 185, 280
Offset: 0

Views

Author

Sung-Hyuk Cha, Mar 07 2014

Keywords

Examples

			Triangle T(n,k) begins:
  0;
  1;
  1, 2;
  1, 3, ;
  1, 3, 4, 7, 12;
  1, 3, 5, 8, 11, 18, 30;
  1, 3, 5, 6,  8, 12, 15, 19, 24, 38, 60;
  ...
		

Crossrefs

Cf. A238946 in graded colexicographic order.

Programs

  • PARI
    \\ here b(n) is A238946.
    b(n)={if(n==1, 0, my(v=vector(bigomega(n))); fordiv(n, d, if(d>1, v[bigomega(d)] += omega(d))); vecmax(v))}
    N(sig)={prod(k=1, #sig, prime(k)^sig[k])}
    Row(n)={apply(s->b(N(s)), [Vecrev(p) | p<-partitions(n)])}
    { for(n=0, 6, print(Row(n))) } \\ Andrew Howroyd, Apr 25 2020

Formula

T(n,k) = A238946(A036035(n,k)).

Extensions

Offset changed and terms a(50) and beyond from Andrew Howroyd, Apr 25 2020

A238968 Maximal level size of arcs in divisor lattice in canonical order.

Original entry on oeis.org

0, 1, 1, 2, 1, 3, 6, 1, 3, 4, 7, 12, 1, 3, 5, 8, 11, 18, 30, 1, 3, 5, 8, 6, 12, 19, 15, 24, 38, 60, 1, 3, 5, 8, 7, 13, 20, 16, 19, 30, 46, 37, 58, 90, 140, 1, 3, 5, 8, 7, 13, 20, 8, 17, 20, 31, 47, 23, 36, 43, 66, 100, 52, 80, 122, 185, 280
Offset: 0

Views

Author

Sung-Hyuk Cha, Mar 07 2014

Keywords

Examples

			Triangle T(n,k) begins:
  0;
  1;
  1, 2;
  1, 3, 6;
  1, 3, 4, 7, 12;
  1, 3, 5, 8, 11, 18, 30;
  1, 3, 5, 8,  6, 12, 19, 15, 24, 38, 60;
  ...
		

Crossrefs

Cf. A238955 in canonical order.

Programs

  • PARI
    \\ here b(n) is A238946.
    b(n)={if(n==1, 0, my(v=vector(bigomega(n))); fordiv(n, d, if(d>1, v[bigomega(d)] += omega(d))); vecmax(v))}
    N(sig)={prod(k=1, #sig, prime(k)^sig[k])}
    Row(n)={apply(s->b(N(s)), vecsort([Vecrev(p) | p<-partitions(n)], , 4))}
    { for(n=0, 8, print(Row(n))) } \\ Andrew Howroyd, Mar 28 2020

Formula

T(n,k) = A238946(A063008(n,k)). - Andrew Howroyd, Mar 28 2020

Extensions

Offset changed and terms a(50) and beyond from Andrew Howroyd, Mar 28 2020
Showing 1-2 of 2 results.