OFFSET
1,1
COMMENTS
Eggleton et al. show that k is in this sequence if and only if A277515(k) > 3.
REFERENCES
R. B. Eggleton, J. S. Kimberley, and J. A. MacDougall, Square-free rank of integers, submitted.
LINKS
Jason Kimberley, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, Beatty Sequence.
FORMULA
EXAMPLE
a(4) = 3*4 + 9 because 9^2 = 81 < 6*4^2 = 96 < 100 = 10^2.
MATHEMATICA
Floor[Range[100]*(3 + Sqrt[6])] (* Paolo Xausa, Jul 11 2024 *)
PROG
(Magma) [3*n+Isqrt(6*n^2): n in [1..60]];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jason Kimberley, Oct 26 2016
STATUS
approved