A389982 Triangle in which row n contains values from 1 to n in alphabetical order (in German).

1, 1, 2, 3, 1, 2, 3, 1, 4, 2, 3, 1, 5, 4, 2, 3, 1, 5, 6, 4, 2, 3, 1, 5, 6, 7, 4, 2, 8, 3, 1, 5, 6, 7, 4, 2, 8, 3, 1, 5, 9, 6, 7, 4, 2, 8, 3, 1, 5, 9, 6, 7, 4, 10, 2, 8, 3, 1, 11, 5, 9, 6, 7, 4, 10, 2, 8, 3, 1, 11, 5, 9, 6, 7, 4, 10, 2, 12, 8, 3, 13, 1, 11, 5, 9, 6, 7, 4, 10, 2, 12

Offset

1,3

Links

Table of n, a(n) for n=1..91.

Formula

Sum_{k=1..n} a(k)/n ~ n/6.

Example

The triangle begins:
  1;
  1, 2;
  3, 1, 2;
  3, 1, 4, 2;
  3, 1, 5, 4, 2;
  3, 1, 5, 6, 4, 2;
  3, 1, 5, 6, 7, 4, 2;
  8, 3, 1, 5, 6, 7, 4, 2;
  8, 3, 1, 5, 9, 6, 7, 4, 2;

Crossrefs

Cf. A001061, A124172.

Sequence in context: A371822 A194862 A194832 * A195107 A054073 A194871

Adjacent sequences: A389979 A389980 A389981 * A389983 A389984 A389985

Keyword

nonn,tabl,word

Author

Johann Peters, Oct 20 2025

Status

approved