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.

A343835 Irregular table T(n, k), n > 0, k = 1..A069010(n), read by rows; the n-th row contains the shortest partition of n whose values belong to A023758 and can be added without carriers in binary, in descending order.

Original entry on oeis.org

1, 2, 3, 4, 4, 1, 6, 7, 8, 8, 1, 8, 2, 8, 3, 12, 12, 1, 14, 15, 16, 16, 1, 16, 2, 16, 3, 16, 4, 16, 4, 1, 16, 6, 16, 7, 24, 24, 1, 24, 2, 24, 3, 28, 28, 1, 30, 31, 32, 32, 1, 32, 2, 32, 3, 32, 4, 32, 4, 1, 32, 6, 32, 7, 32, 8, 32, 8, 1, 32, 8, 2, 32, 8, 3
Offset: 1

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Author

Rémy Sigrist, May 01 2021

Keywords

Comments

In other words, the n-th row gives the numerical values of the runs of 1's in the binary expansion of n.

Examples

			Table begins:
     1:   [1]
     2:   [2]
     3:   [3]
     4:   [4]
     5:   [4, 1]
     6:   [6]
     7:   [7]
     8:   [8]
     9:   [8, 1]
    10:   [8, 2]
    11:   [8, 3]
    12:   [12]
    13:   [12, 1]
    14:   [14]
    15:   [15]
Table begins in binary:
       1:   [1]
      10:   [10]
      11:   [11]
     100:   [100]
     101:   [100, 1]
     110:   [110]
     111:   [111]
    1000:   [1000]
    1001:   [1000, 1]
    1010:   [1000, 10]
    1011:   [1000, 11]
    1100:   [1100]
    1101:   [1100, 1]
    1110:   [1110]
    1111:   [1111]
		

Crossrefs

Programs

  • PARI
    row(n) = { my (rr=[]); while (n, my (z=valuation(n, 2), o=valuation(n/2^z+1, 2), r=(2^o-1)*2^z); n-=r; rr = concat(r, rr);); rr }

Formula

T(n, 1) = A342126(n).
T(n, A069010(n)) = A342410(n).
Sum_{k = 1..A069010(n)} T(n, k) = n.