OFFSET
0,2
COMMENTS
The same sequence, but without the initial 0, obeis the rule: "The concatenation of a(n) and a(a(n)) is even". Example: "2" and the 2nd term, concatenated, is 24; "4" and the 4th term, concatenated, is 46; "1" and the 1st term, concatenated, is 12; etc. - Eric Angelini, Feb 22 2017
LINKS
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, arXiv:math/0305308 [math.NT], 2003.
Index entries for linear recurrences with constant coefficients, signature (0,0,0,2,0,0,0,-1).
FORMULA
For n >= 4 a(n) is given by: a(4m)=6m, a(4m+1)=4m+3, a(4m+2)=6m+2, a(4m+3)=6m+4.
From Chai Wah Wu, Apr 13 2024: (Start)
a(n) = 2*a(n-4) - a(n-8) for n > 11.
G.f.: x*(-3*x^10 + 2*x^9 - x^8 + 8*x^6 + 3*x^4 + 6*x^3 + x^2 + 4*x + 2)/(x^8 - 2*x^4 + 1). (End)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
N. J. A. Sloane, Mar 14 2003
EXTENSIONS
More terms from Matthew Vandermast, Mar 21 2003
STATUS
approved