A026354 a(n) = a(m) if a(m) has already occurred exactly once and n = a(m)+m-2, else a(n) = least positive integer that has not yet occurred.

1, 2, 3, 3, 4, 5, 4, 6, 5, 7, 8, 6, 9, 10, 7, 11, 8, 12, 13, 9, 14, 10, 15, 16, 11, 17, 18, 12, 19, 13, 20, 21, 14, 22, 23, 15, 24, 16, 25, 26, 17, 27, 18, 28, 29, 19, 30, 31, 20, 32, 21, 33, 34, 22, 35, 23, 36, 37, 24, 38, 39, 25, 40, 26, 41, 42

Offset

1,2

Links

Table of n, a(n) for n=1..66.

Jeffrey Shallit, Automaton for a(n)

Formula

a(n)=n for n<4, a(n)=A026242(n-2)+2 for all n>2, a(n)=A026272(n-4)+3 for n>4. - M. F. Hasler, Sep 17 2014

There is a 35-state automaton that accepts, in parallel, the Fibonacci (Zeckendorf) representation of n and a(n). See the file a026354.pdf. - Jeffrey Shallit, Dec 21 2023

Prog

(PARI) A026354=vector(2+#A026242, n, if(n>3, A026242[n-2]+2, n)) \\ Assumes the vector A026242 is defined, see there for PARI code. - M. F. Hasler, Sep 17 2014

Crossrefs

Cf. A026272.

Sequence in context: A115728 A188553 A335680 * A375464 A179840 A374131

Adjacent sequences: A026351 A026352 A026353 * A026355 A026356 A026357

Keyword

nonn

Author

Clark Kimberling

Status

approved