cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-4 of 4 results.

A296712 Numbers whose base-10 digits d(m), d(m-1), ..., d(0) have #(rises) = #(falls); see Comments.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 44, 55, 66, 77, 88, 99, 101, 102, 103, 104, 105, 106, 107, 108, 109, 111, 120, 121, 130, 131, 132, 140, 141, 142, 143, 150, 151, 152, 153, 154, 160, 161, 162, 163, 164, 165, 170, 171, 172, 173, 174, 175, 176, 180, 181
Offset: 1

Views

Author

Clark Kimberling, Jan 08 2018

Keywords

Comments

A rise is an index i such that d(i) < d(i+1); a fall is an index i such that d(i) > d(i+1). The sequences A296712-A296714 partition the natural numbers.
****
Guide to related sequences:
Base #(rises) = #(falls) #(rises) > #(falls) #(rises) < #(falls)
2 A005408 (none) A005843

Examples

			The base-10 digits of 181 are 1,8,1; here #(rises) = 1 and #(falls) = 1, so 181 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 10; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296712 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296713 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296714 *)

A296707 Numbers whose base-8 digits d(m), d(m-1), ..., d(0) have #(rises) > #(falls); see Comments.

Original entry on oeis.org

10, 11, 12, 13, 14, 15, 19, 20, 21, 22, 23, 28, 29, 30, 31, 37, 38, 39, 46, 47, 55, 74, 75, 76, 77, 78, 79, 82, 83, 84, 85, 86, 87, 91, 92, 93, 94, 95, 100, 101, 102, 103, 109, 110, 111, 118, 119, 127, 147, 148, 149, 150, 151, 155, 156, 157, 158, 159, 164
Offset: 1

Views

Author

Clark Kimberling, Jan 08 2018

Keywords

Comments

A rise is an index i such that d(i) < d(i+1); a fall is an index i such that d(i) > d(i+1). The sequences A296706-A296707 partition the natural numbers. See the guide at A296712.

Examples

			The base-8 digits of 164 are 2,4,4; here #(rises) = 1 and #(falls) = 0, so 164 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 8; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296706 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296707 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296708 *)

A296710 Numbers whose base-9 digits d(m), d(m-1), ..., d(0) have #(rises) > #(falls); see Comments.

Original entry on oeis.org

11, 12, 13, 14, 15, 16, 17, 21, 22, 23, 24, 25, 26, 31, 32, 33, 34, 35, 41, 42, 43, 44, 51, 52, 53, 61, 62, 71, 92, 93, 94, 95, 96, 97, 98, 101, 102, 103, 104, 105, 106, 107, 111, 112, 113, 114, 115, 116, 121, 122, 123, 124, 125, 131, 132, 133, 134, 141, 142
Offset: 1

Views

Author

Clark Kimberling, Jan 08 2018

Keywords

Comments

A rise is an index i such that d(i) < d(i+1); a fall is an index i such that d(i) > d(i+1). The sequences A296709-A296711 partition the natural numbers. See the guide at A296712.

Examples

			The base-9 digits of 142 are 1,6,7; here #(rises) = 2 and #(falls) = 0, so 142 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 9; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296709 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296710 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296711 *)

A296711 Numbers whose base-9 digits d(m), d(m-1), ..., d(0) have #(rises) < #(falls); see Comments.

Original entry on oeis.org

9, 18, 19, 27, 28, 29, 36, 37, 38, 39, 45, 46, 47, 48, 49, 54, 55, 56, 57, 58, 59, 63, 64, 65, 66, 67, 68, 69, 72, 73, 74, 75, 76, 77, 78, 79, 81, 90, 162, 171, 172, 180, 181, 243, 252, 253, 261, 262, 263, 270, 271, 272, 324, 333, 334, 342, 343, 344, 351
Offset: 1

Views

Author

Clark Kimberling, Jan 08 2018

Keywords

Comments

A rise is an index i such that d(i) < d(i+1); a fall is an index i such that d(i) > d(i+1). The sequences A296709-A296711 partition the natural numbers. See the guide at A296712.

Examples

			The base-9 digits of 351 are 4,3,0; here #(rises) = 0 and #(falls) = 2, so 351 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 9; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296709 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296710 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296711 *)
Showing 1-4 of 4 results.