A358469 Number of 2's that appeared in the n-th step when constructing A030717.

0, 0, 1, 1, 1, 0, 0, 0, 1, 2, 2, 1, 1, 1, 1, 2, 2, 3, 4, 3, 1, 2, 3, 6, 5, 5, 3, 5, 7, 8, 8, 8, 7, 7, 8, 7, 9, 8, 7, 9, 12, 13, 14, 14, 15, 16, 17, 16, 18, 20, 22, 21, 22, 23, 26, 26, 27, 28, 31, 31, 32, 32, 33, 34, 34, 35, 36, 36, 36, 37, 38, 37, 38, 38, 38, 39, 41, 42, 44, 45, 47, 47, 48, 49, 49, 49, 51, 53, 56, 56, 58, 60, 61, 62, 65

Offset: 1

Author

Seiichi Manyama, Nov 18 2022

Keywords

• nonn

Comments

Also first differences of A358468.

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..1024

Crossrefs

Cf. A030717, A358467, A358468.

Programs

Mathematica

nn = 94; c[] = 0; k = a[1] = c[1] = 1; Prepend[Reap[Do[w = Union@ Array[a, k]; t = 0; Do[Set[a[j + k], c[w[[j]]]]; If[a[j + k] == 2, t++], {j, Length[w]}]; Do[c[a[j + k]]++, {j, Length[w]}]; k += Length[w]; Sow[t], {n, nn}]][[-1, -1]], 0] (* _Michael De Vlieger, Nov 18 2022 *)