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A167411
a(n) = the minimal K value for the orderly number A167408(n).
4
2, 3, 3, 5, 5, 7, 3, 7, 11, 3, 17, 7, 3, 5, 3, 29, 5, 5, 3, 41, 3, 7, 3, 5, 5, 3, 59, 5, 7, 3, 13, 71, 7, 7, 3, 5, 3, 5, 3, 101, 3, 107, 3, 7, 5, 7, 5, 3, 5, 3, 137, 3, 149, 5, 5, 11, 7, 7, 3, 3, 5, 5, 3, 179, 7, 3, 191, 3, 197, 5, 11, 5, 13, 3, 227, 3, 7, 5, 3, 239, 7, 7, 5, 3, 11, 3, 3, 5, 3
OFFSET
1,1
EXAMPLE
a(6) = 7, because A167408(6) = 9, and divisors of 9 = {1,9,3} == {1,2,3} mod 7.
MATHEMATICA
orderlyQkValue[n_] := (For[dd = Divisors[n]; tau = Length[dd]; k = 2, k <= Max[tau + 4, Last[dd] - 2], k++, If[Union[Mod[dd, k]] == Range[tau], Return[{True, k}]]]; {False, 0}); A167411List = Select[{#, orderlyQkValue[#]}& /@ Range[400] , #[[2, 1]]&][[All, 2, 2]] (* Jean-François Alcover, Nov 03 2016 *)
CROSSREFS
Cf. A167408 - Orderly Numbers.
Cf. A167409 - Very Orderly Numbers ( K = tau(N)+1 ).
Cf. A167410 - Disorderly Numbers - numbers not in A167408.
Sequence in context: A093505 A238527 A146071 * A340195 A340192 A363321
KEYWORD
nonn
AUTHOR
Andrew Weimholt, Nov 03 2009
STATUS
approved