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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A353036 Records in A119435.

Original entry on oeis.org

1, 2, 5, 9, 13, 17, 23, 29, 33, 43, 51, 53, 61, 65, 83, 95, 107, 113, 125, 129, 163, 183, 199, 203, 219, 233, 237, 253, 257, 323, 359, 383, 407, 419, 443, 449, 473, 485, 509, 513, 643, 711, 751, 783, 791, 823, 851, 859, 891, 913, 921, 953, 981, 989, 1021, 1025
Offset: 1

Views

Author

Michael De Vlieger, Apr 18 2022

Keywords

Comments

Terms are odd except for a(2) = 2.
(2^k - 1) +- 2 are terms in this sequence for k > 1.
Let S = A119435. S(2^k + 1) = S(2^k - 1) + 4, while S(2^k) is a local minimum in S.
S(2^k - 1) = 2^(k+1) - 3 and S(2^k + 1) = 2^(k+1) + 1.

Crossrefs

Programs

  • Mathematica
    a = {1}; nn = 514; r = 0; Do[AppendTo[a, Complement[Range[i + 2 nn], a][[IntegerReverse[i, 2]] ]], {i, 2, nn}]; Reap[Do[If[# > r, r = #; Sow[r]] &@ a[[i]], {i, Length[a]}]][[-1, -1]]

A353037 Positions of records in A119435.

Original entry on oeis.org

1, 2, 3, 5, 7, 9, 11, 15, 17, 19, 23, 27, 31, 33, 35, 39, 47, 55, 63, 65, 67, 71, 79, 87, 95, 111, 119, 127, 129, 131, 135, 143, 159, 175, 191, 207, 223, 239, 255, 257, 259, 263, 271, 287, 303, 319, 351, 367, 383, 415, 431, 447, 479, 495, 511, 513, 515, 519, 527
Offset: 1

Views

Author

Michael De Vlieger, Apr 18 2022

Keywords

Comments

Let S = A119435. S(2^k +- 1) with k > 0 are records in S and thus (2^k - 1) and (2^k + 1) appear in this sequence.
S(2^k - 1) = 2^(k+1) - 3 and S(2^k + 1) = 2^(k+1) + 1, while S(2^k) is a local minimum.

Crossrefs

Programs

  • Mathematica
    a = {1}; nn = 527; r = 0; Do[AppendTo[a, Complement[Range[i + 2 nn], a][[IntegerReverse[i, 2]] ]], {i, 2, nn}]; Reap[Do[If[# > r, r = #; Sow[i]] &@ a[[i]], {i, Length[a]}]][[-1, -1]]
Showing 1-2 of 2 results.