A250983 - OEIS

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

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

MATHEMATICA

w = {1, 2, 2};

i = 3;

Do[

w = Join[w, Array[Length[w] + 1 &, w[[i++]]]];

, {n, 10}

];

PROG

(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

CROSSREFS

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

Sequence in context: A198332 A080606 A083535 * A070320 A124195 A220662

Adjacent sequences: A250980 A250981 A250982 * A250984 A250985 A250986

KEYWORD

nonn,easy

AUTHOR

Ivan Neretin, Mar 20 2015

EXTENSIONS

More terms from Michel Marcus, Mar 24 2015

STATUS

approved