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A277644 Beatty sequence for sqrt(6)/2. 3
1, 2, 3, 4, 6, 7, 8, 9, 11, 12, 13, 14, 15, 17, 18, 19, 20, 22, 23, 24, 25, 26, 28, 29, 30, 31, 33, 34, 35, 36, 37, 39, 40, 41, 42, 44, 45, 46, 47, 48, 50, 51, 52, 53, 55, 56, 57, 58, 60, 61, 62, 63, 64, 66, 67, 68, 69, 71, 72, 73, 74, 75, 77, 78, 79, 80, 82, 83, 84, 85, 86 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

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

FORMULA

a(n) = floor(n*sqrt(6)/2).

a(n) = A000196(A032528(n)).

EXAMPLE

a(5)=6 because the quotient of 3*5^2 by 2 is 37 which lies between 6^2 and 7^2.

PROG

(MAGMA) [Isqrt(3*n^2 div 2): n in [1..60]];

CROSSREFS

Complement of A277645.

Sequence in context: A039258 A187968 A176253 * A039199 A172269 A115180

Adjacent sequences:  A277641 A277642 A277643 * A277645 A277646 A277647

KEYWORD

nonn,easy

AUTHOR

Jason Kimberley, Oct 26 2016

STATUS

approved

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Last modified March 19 11:29 EDT 2019. Contains 321329 sequences. (Running on oeis4.)