

A080727


a(0) = 1; for n>0, a(n) is taken to be the smallest positive integer greater than a(n1) which is consistent with the condition "n is a member of the sequence if and only if a(n) == 2 mod 3".


0



1, 2, 5, 6, 7, 8, 11, 14, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 29, 32, 35, 38, 41, 44, 47, 50, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 83, 86, 89, 92, 95, 98, 101, 104, 107, 110, 113, 116, 119, 122
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OFFSET

0,2


REFERENCES

HsienKuei 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/wpcontent/files/2016/12/aathhrr1.pdf. Also Exact and Asymptotic Solutions of a DivideandConquer 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=0..67.
B. Cloitre, N. J. A. Sloane and M. J. Vandermast, Numerical analogues of Aronson's sequence, J. Integer Seqs., Vol. 6 (2003), #03.2.2.
B. Cloitre, N. J. A. Sloane and M. J. Vandermast, Numerical analogues of Aronson's sequence (math.NT/0305308)
Index entries for sequences of the a(a(n)) = 2n family


FORMULA

a(a(n)) = 3*n+2, n >= 0.


PROG

(PARI) {a=1; m=[]; for(n=1, 69, print1(a, ", "); a=a+1; if(a%3==2&&a==n, qwqw=qwqw, if(m==[], while(a%3!=2&&a==n, a++), if(m[1]==n, while(a%3!=2, a++); m=if(length(m)==1, [], vecextract(m, "2..")), if(a%3==2, a++))); m=concat(m, a)))}


CROSSREFS

Cf. A079000, A080720, ...
Sequence in context: A074940 A028752 A028791 * A283974 A028739 A074291
Adjacent sequences: A080724 A080725 A080726 * A080728 A080729 A080730


KEYWORD

nonn,easy


AUTHOR

N. J. A. Sloane, Mar 08 2003


EXTENSIONS

More terms and PARI code from Klaus Brockhaus, Mar 09 2003


STATUS

approved



