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A277569
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Numbers n such that n/6^m == 3 (mod 6), where 6^m is the greatest power of 6 that divides n.
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7
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3, 9, 15, 18, 21, 27, 33, 39, 45, 51, 54, 57, 63, 69, 75, 81, 87, 90, 93, 99, 105, 108, 111, 117, 123, 126, 129, 135, 141, 147, 153, 159, 162, 165, 171, 177, 183, 189, 195, 198, 201, 207, 213, 219, 225, 231, 234, 237, 243, 249, 255, 261, 267, 270, 273, 279
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OFFSET
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1,1
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COMMENTS
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Positions of 3 in A277544.
Numbers having 3 as rightmost nonzero digit in base 6. This is one sequence in a 5-way splitting of the positive integers; the other four are indicated in the Mathematica program. Every term is a multiple of 3; see A277573.
Numbers m having the property that tau(3m) < tau(2m) where tau(m) = A000005(m) (i.e., the number of divisors of m). - Gary Detlefs, Jan 28 2019
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LINKS
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Clark Kimberling, Table of n, a(n) for n = 1..10000
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FORMULA
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a(n) = 5n + O(log n). - Charles R Greathouse IV, Nov 03 2016
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MAPLE
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with(numtheory): for n from 1 to 279 do if tau(3*n)<tau(2*n) then print(n) fi od # Gary Detlefs, Jan 28 2019
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MATHEMATICA
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z = 260; a[b_] := Table[Mod[n/b^IntegerExponent[n, b], b], {n, 1, z}]
p[b_, d_] := Flatten[Position[a[b], d]]
p[6, 1] (* A277567 *)
p[6, 2] (* A277568 *)
p[6, 3] (* A277569 *)
p[6, 4] (* A277570 *)
p[6, 5] (* A277571 *)
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PROG
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(PARI) is(n)=(n/6^valuation(n, 6))%6==3 \\ Charles R Greathouse IV, Nov 03 2016
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CROSSREFS
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Cf. A277544, A277567, A277568, A277573.
Sequence in context: A100331 A155764 A259754 * A310329 A310330 A071123
Adjacent sequences: A277566 A277567 A277568 * A277570 A277571 A277572
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KEYWORD
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nonn,easy
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AUTHOR
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Clark Kimberling, Nov 01 2016
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STATUS
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approved
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