A250983 First differences of A094589.

1, 2, 2, 4, 4, 6, 6, 6, 6, 10, 10, 10, 10, 14, 14, 14, 14, 14, 14, 20, 20, 20, 20, 20, 20, 26, 26, 26, 26, 26, 26, 32, 32, 32, 32, 32, 32, 38, 38, 38, 38, 38, 38, 38, 38, 38, 38, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 58, 58, 58, 58, 58, 58, 58, 58, 58, 58

Offset: 1

Author

Ivan Neretin, Mar 20 2015

Keywords

• nonn
• easy

Comments

Also, a Golomb-type sequence over A094589, i.e., a sequence obtained from A094589 by repeating each term a certain number of times so that the succession of run lengths of the resulting sequence is again that same sequence.

Has the property of idempotence: a(a(n))=a(n).

Links

• Ivan Neretin, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A094589 (a(n) with repetitions removed), A001462 (Golomb's sequence), A013189 (Golomb's sequence over squares).

Programs

Mathematica

w = {1, 2, 2};
i = 3;
Do[
  w = Join[w, Array[Length[w] + 1 &, w[[i++]]]];
  , {n, 10}
  ];
w

PARI

flargest(va, n) = {vsa = vecsort(va,,12); for (k=1, #vsa, if (vsa[k] < n, return (vsa[k])););}
lista(nn) = {voa = [1]; for (n=2, nn, newoa = flargest(voa, n) + voa[n-1]; print1(newoa - voa[n-1], ", "); voa = concat(voa, newoa););} \\ Michel Marcus, Mar 24 2015

Extensions

More terms from Michel Marcus, Mar 24 2015