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A329990
Beatty sequence for the number x satisfying 1/x + 1/3^x = 1.
3
1, 2, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15, 17, 18, 19, 20, 22, 23, 24, 26, 27, 28, 30, 31, 32, 34, 35, 36, 38, 39, 40, 41, 43, 44, 45, 47, 48, 49, 51, 52, 53, 55, 56, 57, 58, 60, 61, 62, 64, 65, 66, 68, 69, 70, 72, 73, 74, 76, 77, 78, 79, 81, 82, 83, 85, 86
OFFSET
1,2
COMMENTS
Let x be the solution of 1/x + 1/3^x = 1. Then (floor(n x)) and (floor(n 3^x)) are a pair of Beatty sequences; i.e., every positive integer is in exactly one of the sequences. See the Guide to related sequences at A329825.
FORMULA
a(n) = floor(n x), where x = 1.31056994... is the constant in A329989.
MATHEMATICA
r = x /. FindRoot[1/x + 1/3^x == 1, {x, 1, 10}, WorkingPrecision -> 120]
RealDigits[r][[1]] (* A329989 *)
Table[Floor[n*r], {n, 1, 250}] (* A329990 *)
Table[Floor[n*2^r], {n, 1, 250}] (* A329991 *)
CROSSREFS
Cf. A329825, A329989, A329991 (complement).
Sequence in context: A184480 A194375 A188222 * A109237 A164087 A187386
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jan 02 2020
STATUS
approved