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 1-3 of 3 results.

A352575 A109812(n) in binary.

Original entry on oeis.org

1, 10, 100, 11, 1000, 101, 1010, 10000, 110, 1001, 10010, 1100, 10001, 1110, 100000, 111, 11000, 100001, 10100, 1011, 100100, 10011, 101000, 10101, 100010, 1101, 110000, 1111, 1000000, 10110, 101001, 1000010, 11001, 100110, 1000001, 11010, 100101, 1001000, 10111, 1100000, 11011, 1000100, 100011, 11100, 1000011, 101100, 1010000, 100111, 1011000, 10000000
Offset: 1

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Author

N. J. A. Sloane, Apr 04 2022

Keywords

Crossrefs

Programs

A352884 Binary weight of A109812(n).

Original entry on oeis.org

1, 1, 1, 2, 1, 2, 2, 1, 2, 2, 2, 2, 2, 3, 1, 3, 2, 2, 2, 3, 2, 3, 2, 3, 2, 3, 2, 4, 1, 3, 3, 2, 3, 3, 2, 3, 3, 2, 4, 2, 4, 2, 3, 3, 3, 3, 2, 4, 3, 1, 4, 3, 2, 4, 3, 2, 4, 3, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 2, 4, 3, 3, 4, 2, 5, 2, 4, 2, 4, 3, 3, 4, 3, 4, 3, 3, 4, 3, 4, 3, 4, 3, 4, 3, 3, 4, 3, 3, 4, 3, 5, 1, 5, 3
Offset: 1

Views

Author

Antti Karttunen, Apr 07 2022

Keywords

Comments

Equivalently, binary weight of A352575.

Crossrefs

Programs

  • PARI
    v109812 = readvec("b109812_to10e5.txt"); \\ Prepared from b-file data with gawk ' { print $2 } '
    up_to = #v109812;
    A109812(n) = v109812[n];
    A352884(n) = hammingweight(A109812(n));

Formula

a(n) = A000120(A109812(n)) = A000120(A351965(n)).

A352999 a(n) is the least k > 0 such that A109812(n) and A109812(n + 2*k) have different binary lengths.

Original entry on oeis.org

1, 2, 1, 1, 2, 1, 1, 1, 1, 3, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 4, 2, 3, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 2, 2, 1, 1, 1, 1, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 1, 1, 1, 4, 1, 3, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 8
Offset: 1

Views

Author

Rémy Sigrist, Apr 14 2022

Keywords

Examples

			For n = 21:
- we have:
      k  bin(A109812(21+2*k))
      -  --------------------
      0                100100
      1                101000
      2                100010
      3                110000
      4               1000000
- so a(21) = 4.
		

Crossrefs

Formula

a(n) <= A352998(n).
Showing 1-3 of 3 results.