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A297247 Up-variation of the base-16 digits of n; see Comments. 4
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,19

COMMENTS

Suppose that a number n has base-b digits b(m), b(m-1), ..., b(0).  The base-b down-variation of n is the sum DV(n,b) of all d(i)-d(i-1) for which d(i) > d(i-1); the base-b up-variation of n is the sum UV(n,b) of all d(k-1)-d(k) for which d(k) < d(k-1).  The total base-b variation of n is the sum TV(n,b) = DV(n,b) + UV(n,b). Every positive integer occurs infinitely many times. See A297330 for a guide to related sequences and partitions of the natural numbers.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..10000

EXAMPLE

20 in base 16: 1,4; here UV = 3, so that a(20) = 3.

MATHEMATICA

g[n_, b_] := Differences[IntegerDigits[n, b]];

b = 16; z = 120; Table[-Total[Select[g[n, b], # < 0 &]], {n, 1, z}];  (* A297246 *)

Table[Total[Select[g[n, b], # > 0 &]], {n, 1, z}]; (* A297247 *)

CROSSREFS

Cf. A297246, A297248, A297330.

Sequence in context: A291579 A274933 A080331 * A167463 A053835 A072965

Adjacent sequences:  A297244 A297245 A297246 * A297248 A297249 A297250

KEYWORD

nonn,base,easy

AUTHOR

Clark Kimberling, Jan 18 2018

STATUS

approved

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Last modified June 17 22:17 EDT 2019. Contains 324200 sequences. (Running on oeis4.)