login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A080702 a(1)=3; for n>1, a(n) = smallest number > a(n-1) such that the condition "if n is in the sequence then a(n) is even" is satisfied. 0
3, 4, 6, 8, 9, 10, 11, 12, 14, 16, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

Hsien-Kuei Hwang, S Janson, TH Tsai, Exact and asymptotic solutions of the recurrence f(n) = f(floor(n/2)) + f(ceiling(n/2)) + g(n): theory and applications, Preprint, 2016; http://140.109.74.92/hk/wp-content/files/2016/12/aat-hhrr-1.pdf. Also Exact and Asymptotic Solutions of a Divide-and-Conquer Recurrence Dividing at Half: Theory and Applications, ACM Transactions on Algorithms, 13:4 (2017), #47; DOI: 10.1145/3127585

LINKS

Table of n, a(n) for n=1..70.

FORMULA

{a(a(n))} = {2i : i >= 3}.

PROG

(PARI) lista(nn) = {v = vector(nn); v[1] = 3; prev = v[1]; for (n=2, nn, new = prev+1; if (vecsearch(vecsort(v, , 8), n) && (new % 2), new ++); v[n] = new; prev = new; ); v; } \\ Michel Marcus, Feb 16 2015

CROSSREFS

Equals A079945(n+1) - 1.

Sequence in context: A099356 A325209 A121543 * A156167 A090864 A118300

Adjacent sequences:  A080699 A080700 A080701 * A080703 A080704 A080705

KEYWORD

nonn,easy

AUTHOR

Benoit Cloitre, Mar 01 2003

EXTENSIONS

More terms from Matthew Vandermast, Mar 05 2003

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 14 03:33 EDT 2021. Contains 343872 sequences. (Running on oeis4.)