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.

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A296868 Numbers whose base-5 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments.

Original entry on oeis.org

26, 27, 28, 29, 51, 52, 53, 54, 57, 58, 59, 76, 77, 78, 79, 82, 83, 84, 88, 89, 101, 102, 103, 104, 107, 108, 109, 113, 114, 119, 131, 132, 133, 134, 137, 138, 139, 143, 144, 149, 151, 152, 153, 154, 256, 257, 258, 259, 262, 263, 264, 268, 269, 274, 276, 277
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 A296867-A296869 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-5 digits of 277 are 2,1,0,2; here #(pits) = 1 and #(peaks) = 0, so 277 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296867, A296869.

Programs

  • Mathematica
    z = 200; b = 5;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296867 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296868 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296869 *)

A296869 Numbers whose base-5 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.

Original entry on oeis.org

35, 36, 40, 41, 42, 45, 46, 47, 48, 65, 66, 67, 70, 71, 72, 73, 95, 96, 97, 98, 160, 161, 165, 166, 167, 170, 171, 172, 173, 175, 180, 181, 190, 191, 192, 195, 196, 197, 198, 200, 205, 206, 210, 211, 212, 220, 221, 222, 223, 225, 230, 231, 235, 236, 237, 240
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 A296867-A296869 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-5 digits of 240 are 1,4,3,0; here #(pits) = 0 and #(peaks) = 1, so 240 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296867, A296868.

Programs

  • Mathematica
    z = 200; b = 5;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296867 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296868 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296869 *)
updnQ[n_]:=Total[Which[#[[1]]<#[[2]]>#[[3]],1,#[[1]]>#[[2]]<#[[3]],-1,True,0]&/@Partition[IntegerDigits[n,5],3,1]]>0; Select[Range[ 250],updnQ] (* Harvey P. Dale, Dec 20 2020 *)

A296870 Numbers whose base-6 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, 42, 43, 44, 45, 46, 47, 50, 51, 52, 53, 57, 58, 59, 64, 65, 71, 72, 78, 79, 84, 85, 86, 87, 88, 89, 93, 94, 95, 100, 101
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 A296870-A296872 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-6 digits of 101 are 2,4,5; here #(pits) = 0 and #(peaks) = 0, so 101 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296871, A296872.

Programs

  • Mathematica
    z = 200; b = 6;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296870 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296871 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296872 *)

A296871 Numbers whose base-6 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments.

Original entry on oeis.org

37, 38, 39, 40, 41, 73, 74, 75, 76, 77, 80, 81, 82, 83, 109, 110, 111, 112, 113, 116, 117, 118, 119, 123, 124, 125, 145, 146, 147, 148, 149, 152, 153, 154, 155, 159, 160, 161, 166, 167, 181, 182, 183, 184, 185, 188, 189, 190, 191, 195, 196, 197, 202, 203
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 A296870-A296872 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-6 digits of 203 are 5,3,5; here #(pits) = 1 and #(peaks) = 0, so 203 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296870, A296872.

Programs

  • Mathematica
    z = 200; b = 6;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296870 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296871 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296872 *)

A296872 Numbers whose base-6 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.

Original entry on oeis.org

48, 49, 54, 55, 56, 60, 61, 62, 63, 66, 67, 68, 69, 70, 90, 91, 92, 96, 97, 98, 99, 102, 103, 104, 105, 106, 132, 133, 134, 135, 138, 139, 140, 141, 142, 174, 175, 176, 177, 178, 264, 265, 270, 271, 272, 276, 277, 278, 279, 282, 283, 284, 285, 286, 288, 294
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 A296870-A296872 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-6 digits of 294 are 1,2,1,0; here #(pits) = 0 and #(peaks) = 1, so 294 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296870, A296871.

Programs

  • Mathematica
    z = 200; b = 6;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296870 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296871 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296872 *)

A296873 Numbers whose base-7 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, 56, 57, 58, 59, 60, 61, 62, 65, 66, 67, 68, 69, 73, 74, 75, 76, 81, 82
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 A296873-A296875 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-7 digits of 82 are 1,4,5; here #(pits) = 0 and #(peaks) = 0, so 82 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296874, A296875.

Programs

  • Mathematica
    z = 200; b = 7;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296873 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296874 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296875 *)

A296874 Numbers whose base-7 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments.

Original entry on oeis.org

50, 51, 52, 53, 54, 55, 99, 100, 101, 102, 103, 104, 107, 108, 109, 110, 111, 148, 149, 150, 151, 152, 153, 156, 157, 158, 159, 160, 164, 165, 166, 167, 197, 198, 199, 200, 201, 202, 205, 206, 207, 208, 209, 213, 214, 215, 216, 221, 222, 223, 246, 247, 248
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 A296873-A296875 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-7 digits of 248 are 5,0,3; here #(pits) = 0 and #(peaks) = 0, so 248 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296873, A296875.

Programs

  • Mathematica
    z = 200; b = 7;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296873 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296874 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296875 *)

A296875 Numbers whose base-7 digits d(m), d(m-1), ..., d(0) have #(pits) < #(peaks); see Comments.

Original entry on oeis.org

63, 64, 70, 71, 72, 77, 78, 79, 80, 84, 85, 86, 87, 88, 91, 92, 93, 94, 95, 96, 119, 120, 121, 126, 127, 128, 129, 133, 134, 135, 136, 137, 140, 141, 142, 143, 144, 145, 175, 176, 177, 178, 182, 183, 184, 185, 186, 189, 190, 191, 192, 193, 194, 231, 232, 233
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 A296873-A296875 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-7 digits of 233 are 4,5,2; here #(pits) = 0 and #(peaks) = 1, so 233 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296873, A296874.

Programs

  • Mathematica
    z = 200; b = 7;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296873 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296874 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296875 *)

A296876 Numbers whose base-8 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, 72, 73, 74
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 A296876-A296878 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-8 digits of 74 are 1,1,2; here #(pits) = 0 and #(peaks) = 0, so 74 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296877, A296878.

Programs

  • Mathematica
    z = 200; b = 8;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296876 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296877 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296878 *)

A296877 Numbers whose base-8 digits d(m), d(m-1), ..., d(0) have #(pits) > #(peaks); see Comments.

Original entry on oeis.org

65, 66, 67, 68, 69, 70, 71, 129, 130, 131, 132, 133, 134, 135, 138, 139, 140, 141, 142, 143, 193, 194, 195, 196, 197, 198, 199, 202, 203, 204, 205, 206, 207, 211, 212, 213, 214, 215, 257, 258, 259, 260, 261, 262, 263, 266, 267, 268, 269, 270, 271, 275, 276
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 A296876-A296878 partition the natural numbers. See the guides at A296882 and A296712.

Examples

			The base-8 digits of 276 are 4,2,4; here #(pits) = 1 and #(peaks) = 0, so 276 is in the sequence.

Links

Crossrefs

Cf. A296882, A296712, A296876, A296878.

Programs

  • Mathematica
    z = 200; b = 8;
d[n_] := Differences[Sign[Differences[IntegerDigits[n, b]]]];
Select[Range [z], Count[d[#], -2] == Count[d[#], 2] &]  (* A296876 *)
Select[Range [z], Count[d[#], -2] < Count[d[#], 2] &]   (* A296877 *)
Select[Range [z], Count[d[#], -2] > Count[d[#], 2] &]   (* A296878 *)
Previous Showing 21-30 of 68 results. Next

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