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 11-16 of 16 results.

A044825 Positive integers having distinct base-14 run lengths.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165, 180, 195, 196, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 226, 241, 256, 271, 286, 301, 316, 331, 346, 361, 376, 391, 392, 407, 420, 421, 422, 423
Offset: 1

Views

Author

Clark Kimberling

Keywords

Examples

			346 = 1AA_14 is in the sequence as it has distinct run lengths of distinct digits (1, 2). - _David A. Corneth_, Jan 04 2021

Links

Crossrefs

Cf. A044813, A044814, A044815, A044816, A044817, A044818, A044819, A044820, A044821, A044822, A044823, A044824, A044825, A044826, A044827 (base 2 to base 16).

A044826 Positive integers having distinct base-15 run lengths.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 225, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 257, 273, 289, 305, 321, 337, 353, 369, 385, 401, 417, 433, 449, 450, 466
Offset: 1

Views

Author

Clark Kimberling

Keywords

Examples

			337 = 177_15 is in the sequence as it has distinct run lengths of distinct digits (1, 2). - _David A. Corneth_, Jan 04 2021

Links

Crossrefs

Cf. A044813, A044814, A044815, A044816, A044817, A044818, A044819, A044820, A044821, A044822, A044823, A044824, A044825, A044826, A044827 (base 2 to base 16).

A044827 Positive integers having distinct base-16 run lengths.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 34, 51, 68, 85, 102, 119, 136, 153, 170, 187, 204, 221, 238, 255, 256, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 290, 307, 324, 341, 358, 375, 392, 409, 426, 443, 460, 477
Offset: 1

Views

Author

Clark Kimberling

Keywords

Examples

			324 = 144_16 is in the sequence as it has distinct run lengths of distinct digits (1, 2). - _David A. Corneth_, Jan 04 2021

Links

Crossrefs

Cf. A044813, A044814, A044815, A044816, A044817, A044818, A044819, A044820, A044821, A044822, A044823, A044824, A044825, A044826, A044827 (base 2 to base 16).

A297139 Numbers whose base-7 digits d(m), d(m-1),..., d(0) have m=0 or else d(i) = d(i+1) for some i in {0,1,...,m-1}.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 8, 16, 24, 32, 40, 48, 49, 56, 57, 58, 59, 60, 61, 62, 65, 73, 81, 89, 97, 98, 106, 112, 113, 114, 115, 116, 117, 118, 122, 130, 138, 146, 147, 155, 163, 168, 169, 170, 171, 172, 173, 174, 179, 187, 195, 196, 204, 212, 220, 224, 225, 226
Offset: 1

Views

Author

Clark Kimberling, Jan 15 2018

Keywords

Comments

These numbers comprise the complement of the set of numbers in the union of A297137 and A297138.
Differs from A044818 first for 344 = 1001_7. 1001_7 has two runs of length 1 and is not in A044818, but it has a sequence of two consecutive zeros and is in this sequence. - R. J. Mathar, Jan 18 2018

Examples

			Base-7 digits of 4998: 2,0,4,0,0, so that 4998 is in the sequence.

Crossrefs

Cf. A297137, A297138.

Programs

  • Maple
    read("transforms") :
isA297139 := proc(n)
        local dgs,ud;
        dgs := convert(n,base,7) ;
        if nops(dgs) < 2 then
                return true;
        end if;
        if 0 in DIFF(dgs) then
                true;
        else
                false;
        end if;
end proc:
for n from 1 to 300 do
        if isA297139(n) then
                printf("%d,",n) ;
        end if;
end do: # R. J. Mathar, Jan 18 2018
  • Mathematica
    a[n_, b_] := Sign[Differences[IntegerDigits[n, b]]]; z = 300;
b = 7; t = Table[a[n, b], {n, 1, 10*z}];
u = Select[Range[z], ! MemberQ[t[[#]], 0] && First[t[[#]]] == 1 &]   (* A297137 *)
v = Select[Range[z], ! MemberQ[t[[#]], 0] && First[t[[#]]] == -1 &]  (* A297138 *)
Complement[Range[z], Union[u, v]]  (* A297139 *)

A048304 Numbers whose base-7 expansions, read from left to right, have run lengths that strictly increase.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 8, 16, 24, 32, 40, 48, 49, 57, 65, 73, 81, 89, 97, 98, 106, 114, 122, 130, 138, 146, 147, 155, 163, 171, 179, 187, 195, 196, 204, 212, 220, 228, 236, 244, 245, 253, 261, 269, 277, 285, 293, 294, 302, 310, 318, 326, 334, 342, 343, 400, 457
Offset: 0

Views

Author

Patrick De Geest, Feb 15 1999

Keywords

Crossrefs

Cf. A037015, A043696, A043710, A044818, A044956.

A048318 Numbers whose base-7 expansions, read from left to right, have run lengths that strictly decrease.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 8, 16, 24, 32, 40, 48, 56, 57, 58, 59, 60, 61, 62, 112, 113, 114, 115, 116, 117, 118, 168, 169, 170, 171, 172, 173, 174, 224, 225, 226, 227, 228, 229, 230, 280, 281, 282, 283, 284, 285, 286, 336, 337, 338, 339, 340, 341, 342, 399, 400, 401
Offset: 0

Views

Author

Patrick De Geest, Feb 15 1999

Keywords

Crossrefs

Cf. A037013, A043696, A043710, A044818, A044956.

Programs

  • Mathematica
    Select[Range[0,500],Max[Differences[Length/@Split[IntegerDigits[ #, 7]]]]<0&] (* Harvey P. Dale, Apr 27 2018 *)
Previous Showing 11-16 of 16 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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