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A277645
Beatty sequence for 3+sqrt(6).
3
5, 10, 16, 21, 27, 32, 38, 43, 49, 54, 59, 65, 70, 76, 81, 87, 92, 98, 103, 108, 114, 119, 125, 130, 136, 141, 147, 152, 158, 163, 168, 174, 179, 185, 190, 196, 201, 207, 212, 217, 223, 228, 234, 239, 245, 250, 256, 261, 267, 272, 277, 283, 288, 294, 299, 305
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.
FORMULA
a(n) = floor(n*(3+sqrt(6))).
a(n) = 3*n + A000196(A033581(n)).
a(n) = A008585(n) + A000196(A033581(n)).
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
Complement of A277644.
Sequence in context: A313894 A276853 A178181 * A075003 A313895 A313896
KEYWORD
nonn,easy
AUTHOR
Jason Kimberley, Oct 26 2016
STATUS
approved