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 1-2 of 2 results.

A123753 Partial sums of A070941.

Original entry on oeis.org

1, 3, 6, 9, 13, 17, 21, 25, 30, 35, 40, 45, 50, 55, 60, 65, 71, 77, 83, 89, 95, 101, 107, 113, 119, 125, 131, 137, 143, 149, 155, 161, 168, 175, 182, 189, 196, 203, 210, 217, 224, 231, 238, 245, 252, 259, 266, 273, 280, 287, 294, 301, 308, 315, 322, 329, 336, 343
Offset: 0

Views

Author

Reinhard Zumkeller, Oct 12 2006

Keywords

Crossrefs

Programs

  • Maple
    A123753 := proc(n) local i, J, z; i := n+1: J := i; i := i-1; z := 1;
    while 0 <= i do J := J+i; i := i-z; z := z+z od; J end:
    seq(A123753(n), n=0..57); # Peter Luschny, Nov 30 2017
    # Alternatively:
    a := n -> (n+1)*(1 + ilog2(2*n+3)) - 2^ilog2(2*n+3) + 1:
    seq(a(n), n=0..57); # Peter Luschny, Dec 02 2017
  • Mathematica
    a[n_] := (n + 1)(1 + IntegerLength[n + 1, 2]) - 2^IntegerLength[n + 1, 2] + 1;
    Table[a[n], {n, 0, 57}] (* Peter Luschny, Dec 02 2017 *)
  • Python
    def A123753(n):
        s, i, z = n+1, n, 1
        while 0 <= i: s += i; i -= z; z += z
        return s
    print([A123753(n) for n in range(0, 58)]) # Peter Luschny, Nov 30 2017
    
  • Python
    def A123753(n): return (n+1)*(1+(m:=n.bit_length()))-(1<Chai Wah Wu, Mar 29 2023

Formula

a(n) = A003314(n+1)+1. - Reinhard Zumkeller, Oct 12 2006
Let bil(n) = floor(log_2(n)) + 1 for n>0, bil(0) = 0 and b(n) = n + n*bil(n) - 2^bil(n) + 1 then a(n) = b(n+1). (This suggests that '0' be prepended to this sequence.) - Peter Luschny, Dec 02 2017

A295513 a(n) = n*bil(n) - 2^bil(n) where bil(0) = 0 and bil(n) = floor(log_2(n)) + 1 for n>0.

Original entry on oeis.org

-1, -1, 0, 2, 4, 7, 10, 13, 16, 20, 24, 28, 32, 36, 40, 44, 48, 53, 58, 63, 68, 73, 78, 83, 88, 93, 98, 103, 108, 113, 118, 123, 128, 134, 140, 146, 152, 158, 164, 170, 176, 182, 188, 194, 200, 206, 212, 218, 224, 230, 236, 242, 248, 254, 260, 266, 272, 278
Offset: 0

Views

Author

Peter Luschny, Dec 02 2017

Keywords

Crossrefs

Programs

  • Maple
    A295513 := proc(n) local i, s, z; s := -1; i := n-1; z := 1;
    while 0 <= i do s := s+i; i := i-z; z := z+z od; s end:
    seq(A295513(n), n=0..57);
  • Mathematica
    a[n_] := n IntegerLength[n, 2] - 2^IntegerLength[n, 2];
    Table[a[n], {n, 0, 58}]
  • Python
    def A295513(n): return n*(m:=(n-1).bit_length())-(1<Chai Wah Wu, Mar 29 2023

Formula

A001855(n) = a(n) + 1.
A033156(n) = a(n) + 2n.
A003314(n) = a(n) + n.
A083652(n) = a(n+1) + 2.
A061168(n) = a(n+1) - n + 1.
A123753(n) = a(n+1) + n + 2.
A097383(n) = a(n+1) - div(n-1, 2).
A054248(n) = a(n) + n + rem(n, 2).
Showing 1-2 of 2 results.