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A297136
Numbers whose base-6 digits d(m), d(m-1), ..., d(0) have m=0 or else d(i) = d(i+1) for some i in {0,1,...,m-1}.
4
1, 2, 3, 4, 5, 7, 14, 21, 28, 35, 36, 42, 43, 44, 45, 46, 47, 50, 57, 64, 71, 72, 79, 84, 85, 86, 87, 88, 89, 93, 100, 107, 108, 115, 122, 126, 127, 128, 129, 130, 131, 136, 143, 144, 151, 158, 165, 168, 169, 170, 171, 172, 173, 179, 180, 187, 194, 201, 208
OFFSET
1,2
COMMENTS
These numbers comprise the complement of the set of numbers in the union of A297134 and A297135.
This first differs from A044817 at position 67: a(67) = 217, A044817(67) = 258. - Robert Israel, Jan 17 2018
LINKS
EXAMPLE
Base-6 digits of 4996: 3,5,0,4,4, so that 4996 is in the sequence.
MAPLE
filter:= proc(n) local L;
L:= convert(n, base, 6);
nops(L)=1 or member(0, L[2..-1]-L[1..-2])
end proc:
select(filter, [$1..1000]); # Robert Israel, Jan 17 2018
MATHEMATICA
a[n_, b_] := Sign[Differences[IntegerDigits[n, b]]]; z = 300;
b = 6; t = Table[a[n, b], {n, 1, 10*z}];
u = Select[Range[z], ! MemberQ[t[[#]], 0] && First[t[[#]]] == 1 &] (* A297134 *)
v = Select[Range[z], ! MemberQ[t[[#]], 0] && First[t[[#]]] == -1 &] (* A297135 *)
Complement[Range[z], Union[u, v]] (* A297136 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Jan 14 2018
STATUS
approved

  NODES
COMMUNITY 1
INTERN 1