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.

Previous Showing 11-20 of 115 results. Next

A296751 Numbers whose base-13 digits d(m), d(m-1), ..., d(0) have #(rises) > #(falls); see Comments.

Original entry on oeis.org

15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 43, 44, 45, 46, 47, 48, 49, 50, 51, 57, 58, 59, 60, 61, 62, 63, 64, 71, 72, 73, 74, 75, 76, 77, 85, 86, 87, 88, 89, 90, 99, 100, 101, 102, 103, 113, 114, 115, 116, 127, 128
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 A296751-A296753 partition the natural numbers. See the guide at A296712.

Examples

			The base-13 digits of 1000 are 5,11,12; here #(rises) = 2 and #(falls) = 0, so 1000 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 13; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296750 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296751 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296752 *)

A296752 Numbers whose base-13 digits d(m), d(m-1), ..., d(0) have #(rises) < #(falls); see Comments.

Original entry on oeis.org

13, 26, 27, 39, 40, 41, 52, 53, 54, 55, 65, 66, 67, 68, 69, 78, 79, 80, 81, 82, 83, 91, 92, 93, 94, 95, 96, 97, 104, 105, 106, 107, 108, 109, 110, 111, 117, 118, 119, 120, 121, 122, 123, 124, 125, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 143, 144
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 A296751-A296753 partition the natural numbers. See the guide at A296712.

Examples

			The base-13 digits of 914 are 5,5,4; here #(rises) = 0 and #(falls) = 1, so 914 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 13; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296750 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296751 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296752 *)

A296754 Numbers whose base-14 digits d(m), d(m-1), ..., d(0) have #(rises) > #(falls); see Comments.

Original entry on oeis.org

16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 61, 62, 63, 64, 65, 66, 67, 68, 69, 76, 77, 78, 79, 80, 81, 82, 83, 91, 92, 93, 94, 95, 96, 97, 106, 107, 108, 109, 110, 111
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 A296753-A296755 partition the natural numbers. See the guide at A296712.

Examples

			The base-14 digits of 10000000 are 1,12,0,6,0,8; here #(rises) = 3 and #(falls) = 2, so 10000000 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 14; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296753 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296754 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296755 *)

A296755 Numbers whose base-14 digits d(m), d(m-1), ..., d(0) have #(rises) < #(falls); see Comments.

Original entry on oeis.org

14, 28, 29, 42, 43, 44, 56, 57, 58, 59, 70, 71, 72, 73, 74, 84, 85, 86, 87, 88, 89, 98, 99, 100, 101, 102, 103, 104, 112, 113, 114, 115, 116, 117, 118, 119, 126, 127, 128, 129, 130, 131, 132, 133, 134, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 154
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 A296753-A296755 partition the natural numbers. See the guide at A296712.

Examples

			The base-14 digits of 10^9 are 9, 6, 11, 4, 11, 6, 11, 6; here #(rises) = 3 and #(falls) = 4, so 10^9 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 14; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296753 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296754 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296755 *)

A296757 Numbers whose base-15 digits d(m), d(m-1), ..., d(0) have #(rises) > #(falls); see Comments.

Original entry on oeis.org

17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 81, 82, 83, 84, 85, 86, 87, 88, 89, 97, 98, 99, 100, 101, 102, 103, 104
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 A296756-A296758 partition the natural numbers. See the guide at A296712.

Examples

			The base-15 digits of 2^20 + 6 are 1, 5, 10, 10, 5, 7; here #(rises) = 3 and #(falls) = 1, so 2^20 + 6 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 15; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296756 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296757 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296758 *)

A296758 Numbers whose base-15 digits d(m), d(m-1), ..., d(0) have #(rises) < #(falls); see Comments.

Original entry on oeis.org

15, 30, 31, 45, 46, 47, 60, 61, 62, 63, 75, 76, 77, 78, 79, 90, 91, 92, 93, 94, 95, 105, 106, 107, 108, 109, 110, 111, 120, 121, 122, 123, 124, 125, 126, 127, 135, 136, 137, 138, 139, 140, 141, 142, 143, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 165
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 A296756-A296758 partition the natural numbers. See the guide at A296712.

Examples

			The base-15 digits of 15^5 are 1, 0, 0, 0, 0, 0; here #(rises) = 0 and #(falls) = 1, so 15^5 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 15; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296756 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296757 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296758 *)

A296760 Numbers whose base-16 digits d(m), d(m-1), ..., d(0) have #(rises) > #(falls); see Comments.

Original entry on oeis.org

18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 103, 104, 105, 106
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 A296759-A296761 partition the natural numbers. See the guide at A296712.

Examples

			The base-16 digits of 106 are 6,10; here #(rises) = 1 and #(falls) = 0, so 106 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 16; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296759 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296760 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296761 *)
    rgf16Q[n_]:=Total[Sign[#]&/@Differences[IntegerDigits[n,16]]]>0;Select[Range[150],rgf16Q] (* Harvey P. Dale, Nov 26 2023 *)

A296761 Numbers whose base-16 digits d(m), d(m-1), ..., d(0) have #(rises) < #(falls); see Comments.

Original entry on oeis.org

16, 32, 33, 48, 49, 50, 64, 65, 66, 67, 80, 81, 82, 83, 84, 96, 97, 98, 99, 100, 101, 112, 113, 114, 115, 116, 117, 118, 128, 129, 130, 131, 132, 133, 134, 135, 144, 145, 146, 147, 148, 149, 150, 151, 152, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169
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 A296759-A296761 partition the natural numbers. See the guide at A296712.

Examples

			The base-16 digits of 32 are 2,0; here #(rises) = 0 and #(falls) = 2, so 32 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 16; d[n_] := Sign[Differences[IntegerDigits[n, b]]];
    Select[Range [z], Count[d[#], -1] == Count[d[#], 1] &] (* A296759 *)
    Select[Range [z], Count[d[#], -1] < Count[d[#], 1] &]  (* A296760 *)
    Select[Range [z], Count[d[#], -1] > Count[d[#], 1] &]  (* A296761 *)

A296879 Numbers whose base-9 digits d(m), d(m-1), ..., d(0) have #(pits) = #(peaks); see Comments.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67
Offset: 1

Views

Author

Clark Kimberling, Jan 09 2018

Keywords

Comments

A pit is an index i such that d(i-1) > d(i) < d(i+1); a peak is an index i such that d(i-1) < d(i) > d(i+1). The sequences A296879-A296881 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-9 digits of 67 are 7,4; here #(pits) = 0 and #(peaks) = 0, so 67 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 9;
    d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
    Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296879 *)
    Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296880 *)
    Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296881 *)

A296885 Numbers whose base-11 digits d(m), d(m-1), ..., d(0) have #(pits) = #(peaks); see Comments.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67
Offset: 1

Views

Author

Clark Kimberling, Jan 10 2018

Keywords

Comments

A pit is an index i such that d(i-1) > d(i) < d(i+1); a peak is an index i such that d(i-1) < d(i) > d(i+1). The sequences A296885-A296887 partition the natural numbers. See the guides at A296712 and A296882.

Examples

			The base-11 digits of 1586 are 1,2,1,2; here #(pits) = 1 and #(peaks) = 1, so 1586 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    z = 200; b = 11;
    d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
    Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296885 *)
    Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296886 *)
    Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296887 *)
Previous Showing 11-20 of 115 results. Next