A055170 -id:A055170 - cp's OEIS frontend

A055168 Cumulative counting sequence: method B (noun,adjective)-pairs with first term 0.

0, 0, 1, 0, 2, 1, 1, 0, 3, 1, 3, 2, 1, 0, 4, 1, 5, 2, 2, 3, 2, 0, 5, 1, 6, 2, 5, 3, 3, 4, 1, 5, 1, 0, 6, 1, 9, 2, 6, 3, 5, 4, 2, 5, 4, 6, 1, 0, 7, 1, 11, 2, 8, 3, 6, 4, 4, 5, 6, 6, 4, 9, 1, 0, 8, 1, 13, 2, 9, 3, 7, 4, 7, 5, 7, 6, 7, 9, 2, 7, 1, 11, 1, 8, 1, 0, 9, 1, 17

Offset: 1

Clark Kimberling, Apr 27 2000

nonn

Write 0 followed by segments defined inductively as follows: each segment tells how many times each previously written integer occurs, stating first the integer being counted and then its frequency. This is Method B (noun-before-adjective); for Method A (adjective-before-noun), see A217760. - Clark Kimberling, Mar 25 2013

			Start with 0, then 0,1; then 2,0 and 1,1; etc.
Writing pairs vertically, the initial segments are
0..0..0 1..0 1 2..0 1 2 3..0 1 2 3 4 5..0 1 2 3 4 5 6..0  1 2 3 4 5 6 9
...1..2 1..3 3 1..4 5 2 2..5 6 5 3 1 1..6 9 6 5 2 4 1..7 11 8 6 4 6 3 1
The 5th segment tells that 0 has been written 4 times, 1 5 times, 2 2 times, and 3 2 times. The nouns are 1 2 3; the adjectives, 5 2 2.  - _Clark Kimberling_, Mar 25 2013

Seiichi Manyama, Table of n, a(n) for n = 1..10000

Cf. A217760, A055170.
Cf. A055171, A055174, A055177, A055180, A055183.
See A001155 and A022470 for well-known counting sequences using methods A and B.

s = {0}; Do[s = Flatten[{s, {#,Count[s, #]} & /@ DeleteDuplicates[s]}], {24}]; s (* Peter J. C. Moses, Mar 21 2013 *)

Conjecture removed by Clark Kimberling, Oct 24 2009

A217760 Cumulative counting sequence: (adjective-before-noun) pairs with first term 0; see Comments.

Original entry on oeis.org

0, 1, 0, 2, 0, 1, 1, 3, 0, 3, 1, 1, 2, 4, 0, 5, 1, 2, 2, 2, 3, 5, 0, 6, 1, 5, 2, 3, 3, 1, 4, 1, 5, 6, 0, 9, 1, 6, 2, 5, 3, 2, 4, 4, 5, 1, 6, 7, 0, 11, 1, 8, 2, 6, 3, 4, 4, 6, 5, 4, 6, 1, 9, 8, 0, 13, 1, 9

Offset: 1

Clark Kimberling, Mar 24 2013

Write 0 followed by segments defined inductively as follows: each segment
tells how many times each previously written integer occurs, in the order
of first occurrence.  This is Method A (adjective-before-noun pairs); for
Method B (noun-before-adjective), see A055168.  The sequence A217760 was
originally A055186 (Apr 27 2000); the present A055186 has a shorter
definition and differs from A217760 beginning at the 62nd term.

			Start with 0, followed by the adjective-noun pair 1,0; followed by
adjective-noun pairs 2,0 then 1,1; etc. Writing the pairs vertically,
the initial segments are
0..1..2 1..3 3 1..4 5 2 2..5 6 5 3 1 1..6 9 6 5 2 4 1..7 11 8 6 4 6 4 1
...0..0 1..0 1 2..0 1 2 3..0 1 2 3 4 5..0 1 2 3 4 5 6..0 1  2 3 4 5 6 9
The order of appearance is 0,1,2,3,4,5,6,9,7,11,8,... conjectured at A055170 to include all the nonnegative integers.

Clark Kimberling, Table of n, a(n) for n = 1..9666
Clark Kimberling, Unsolved Problems and Rewards, Problem 4

Cf. A055170, A055186.

s = {0}; Do[s = Flatten[{s, {Count[s, #], #} & /@ DeleteDuplicates[s]}], {14}]; s  (* A217760 *)
s = {0}; Do[s = Flatten[{s, {Count[s, #], #} & /@ (a = DeleteDuplicates[s])}], {24}]; a;  (* A055170 *) (* Peter J. C. Moses, Mar 21 2013 *)

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A055168 Cumulative counting sequence: method B (noun,adjective)-pairs with first term 0.

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