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.

A060299 Triangle T(m,n), 1 <= n <= m, read by rows: row m lists the first m consecutive composite numbers that are not in previous rows.

Original entry on oeis.org

4, 8, 9, 14, 15, 16, 24, 25, 26, 27, 32, 33, 34, 35, 36, 90, 91, 92, 93, 94, 95, 114, 115, 116, 117, 118, 119, 120, 140, 141, 142, 143, 144, 145, 146, 147, 182, 183, 184, 185, 186, 187, 188, 189, 190, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 212, 213
Offset: 1

Views

Author

Jason Earls, Mar 25 2001

Keywords

Examples

			Triangle starts:
   4;
   8,  9;
  14, 15, 16;
  24, 25, 26, 27;
  32, 33, 34, 35, 36;
  90, 91, 92, 93, 94, 95; - _Robert Israel_, Jan 17 2023
First occurrence of 1 consecutive composite gives 4, first occurrence of 2 consecutive composites gives 8 and 9, the first subsequent, disjoint occurrence of 3 consecutive composites gives 14, 15 and 16, etc.
		

Crossrefs

First column gives A060064.

Programs

  • Maple
    R:= NULL: m:= 1;
    p:= 3:
    while m < 30 do
      q:= nextprime(p);
      g:= q-p-1;
      if g >= m then
        R:= R, $(p+1)..(p+m);
        p:= p+m;
        m:= m+1;
      else
        p:= q
      fi;
    od:
    R; # Robert Israel, Jan 17 2023

Extensions

Name changed by Robert Israel, Jan 17 2023