

A296883


Numbers whose base10 digits d(m), d(m1), ..., d(0) have #(pits) > #(peaks); see Comments.


3



101, 102, 103, 104, 105, 106, 107, 108, 109, 201, 202, 203, 204, 205, 206, 207, 208, 209, 212, 213, 214, 215, 216, 217, 218, 219, 301, 302, 303, 304, 305, 306, 307, 308, 309, 312, 313, 314, 315, 316, 317, 318, 319, 323, 324, 325, 326, 327, 328, 329, 401, 402
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OFFSET

1,1


COMMENTS

A pit is an index i such that d(i1) > d(i) < d(i+1); a peak is an index i such that d(i1) < d(i) > d(i+1). The sequences A296882A296883 partition the natural numbers. See the guides at A296712 and A296882.


LINKS



EXAMPLE

The base10 digits of 21212 are 2,1,2,1,2; here #(pits) = 2 and #(peaks) = 1, so 21212 is in the sequence.


MATHEMATICA

z = 200; b = 10;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], 2] == Count[d[#], 2] &] (* A296882 *)
Select[Range [z], Count[d[#], 2] < Count[d[#], 2] &] (* A296883 *)
Select[Range [z], Count[d[#], 2] > Count[d[#], 2] &] (* A296884 *)


CROSSREFS



KEYWORD

nonn,base,easy


AUTHOR



STATUS

approved



