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A297291 Solution (a(n)) of the system of 3 complementary equations in Comments. 3

%I #4 Apr 25 2018 08:32:51

%S 1,4,5,9,12,13,16,17,21,22,27,28,31,32,37,38,41,44,47,48,51,52,57,58,

%T 61,62,67,68,71,72,77,78,81,84,85,89,90,93,97,98,101,104,107,108,111,

%U 112,117,118,121,122,127,128,131,132,137,138,141,144,147,148

%N Solution (a(n)) of the system of 3 complementary equations in Comments.

%C Define sequences a(n), b(n), c(n) recursively:

%C a(n) = least new;

%C b(n) = least new > = a(n) + 2;

%C c(n) = a(n) + b(n) - 2;

%C where "least new k" means the least positive integer not yet placed.

%C ***

%C The sequences a,b,c partition the positive integers.

%C ***

%C Conjectures: for n >=0,

%C 0 <= 5*n + 4 - 2*a(n) <= 5,

%C 0 <= 5*n + 8 - 2*b(n) <= 4,

%C 0 <= c(n) - 5n <= 4.

%H Clark Kimberling, <a href="/A297291/b297291.txt">Table of n, a(n) for n = 0..1000</a>

%e n: 0 1 2 3 4 5 6 7 8 9 10

%e a: 1 4 5 9 12 13 16 17 21 27 28

%e b: 3 6 7 11 14 15 19 20 23 25 29

%e c: 2 8 10 18 24 26 33 35 42 45 54

%t z = 300;

%t mex[list_, start_] := (NestWhile[# + 1 &, start, MemberQ[list, #] &]);

%t a = b = c = {};

%t Do[{AppendTo[a,

%t mex[Flatten[{a, b, c}], If[Length[a] == 0, 1, Last[a]]]],

%t AppendTo[b, mex[Flatten[{a, b, c}], Last[a] + 2]],

%t AppendTo[c, Last[a] + Last[b] - 2]}, {z}];

%t Take[a, 100] (* A297291 *)

%t Take[b, 100] (* A297292 *)

%t Take[c, 100] (* A297293 *)

%t (* _Peter J. C. Moses_, Apr 23 2018 *)

%Y Cf. A299634, A297292, A297293.

%K nonn,easy

%O 0,2

%A _Clark Kimberling_, Apr 24 2018

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Last modified April 25 05:49 EDT 2024. Contains 371964 sequences. (Running on oeis4.)