A297133 - OEIS

A297133

Numbers whose base-5 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}.

%I #4 Jan 14 2018 23:01:54

%S 1,2,3,4,6,12,18,24,25,30,31,32,33,34,37,43,49,50,56,60,61,62,63,64,

%T 68,74,75,81,87,90,91,92,93,94,99,100,106,112,118,120,121,122,123,124,

%U 125,126,127,128,129,131,137,143,149,150,151,152,153,154,155,156

%N Numbers whose base-5 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}.

%C These numbers comprise the complement of the set of numbers in the union of A297131 and A297132.

%e Base-5 digits of 5000: 1,3,0,0,0,0, so that 5000is in the sequence.

%t a[n_, b_] := Sign[Differences[IntegerDigits[n, b]]]; z = 300;

%t b = 5; t = Table[a[n, b], {n, 1, 10*z}];

%t u = Select[Range[z], ! MemberQ[t[[#]], 0] && First[t[[#]]] == 1 &] (* A297131 *)

%t v = Select[Range[z], ! MemberQ[t[[#]], 0] && First[t[[#]]] == -1 &] (* A297132 *)

%t Complement[Range[z], Union[u, v]] (* A297133 *)

%Y Cf. A297131, A297132.

%K nonn,easy,base

%O 1,2

%A _Clark Kimberling_, Jan 14 2018