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.

A217780 Cumulative counting sequence: (adjective-before-noun) pairs with first term 1.

Original entry on oeis.org

1, 1, 1, 3, 1, 4, 1, 1, 3, 6, 1, 2, 3, 1, 4, 8, 1, 3, 3, 2, 4, 1, 6, 1, 2, 11, 1, 5, 3, 3, 4, 2, 6, 3, 2, 1, 8, 13, 1, 8, 3, 4, 4, 3, 6, 5, 2, 2, 8, 1, 11, 1, 5, 16, 1, 10, 3, 6, 4, 4, 6, 7, 2, 4, 8, 2, 11, 3, 5, 1, 13, 18, 1, 12, 3, 9, 4, 6, 6, 9, 2, 5, 8, 3, 11, 4, 5, 2, 13, 1, 16, 1, 10, 1, 7
Offset: 1

Views

Author

Clark Kimberling, Mar 25 2013

Keywords

Comments

After starting with 1, successive segments are generated in adjective-before-noun pairs as in A217760, not as in A055187. That is, noun-integers occur in order of 1st appearance, not increasing order.

Examples

			Writing pairs vertically, the initial segments are
1..1..3..4 1..6 2 1..8 3 2 1 1..11 5 3 2 3 1
...1..1..1 3..1 3 4..1 3 4 6 2...1 3 4 6 2 8.
The 5th segment is read "6 1's and 2 3's and 1 4," this being a count of all the previously written numbers.  The numbers 6,2,1 are used as adjectives, whereas 1,3,4 are used as nouns.  Here, the nouns are kept in order of first appearance; in A055187, they are in increasing order. - _Clark Kimberling_, Mar 25 2013
		

Crossrefs

Programs

  • Mathematica
    s = {1}; Do[s = Flatten[{s, {Count[s, #], #} & /@ DeleteDuplicates[s]}], {14}]; s (* Peter J. C. Moses, Mar 21 2013 *)

Extensions

More terms from Seiichi Manyama, Nov 10 2022