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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A350673 Square array read by antidiagonals T(n, k), n, k >= 0; T(n, k) is the sum of the elements of the intersection of the multisets of positive squares summing to n and k, respectively, obtained by the greedy algorithm.

Original entry on oeis.org

0, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 2, 1, 0, 0, 0, 2, 2, 0, 0, 0, 1, 0, 3, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 2, 1, 4, 1, 2, 1, 0, 0, 0, 2, 2, 4, 4, 2, 2, 0, 0, 0, 0, 0, 3, 4, 5, 4, 3, 0, 0, 0, 0, 1, 0, 0, 4, 5, 5, 4, 0, 0, 1, 0, 0, 1, 1, 0, 4, 5, 6, 5, 4, 0, 1, 1, 0
Offset: 0

Views

Author

Rémy Sigrist, Jan 10 2022

Keywords

Examples

			Array T(n, k) begins:
  n\k|  0  1  2  3  4  5  6  7  8  9  10
  ---+----------------------------------
    0|  0  0  0  0  0  0  0  0  0  0   0
    1|  0  1  1  1  0  1  1  1  0  0   1
    2|  0  1  2  2  0  1  2  2  0  0   1
    3|  0  1  2  3  0  1  2  3  0  0   1
    4|  0  0  0  0  4  4  4  4  4  0   0
    5|  0  1  1  1  4  5  5  5  4  0   1
    6|  0  1  2  2  4  5  6  6  4  0   1
    7|  0  1  2  3  4  5  6  7  4  0   1
    8|  0  0  0  0  4  4  4  4  8  0   0
    9|  0  0  0  0  0  0  0  0  0  9   9
   10|  0  1  1  1  0  1  1  1  0  9  10
		

Crossrefs

Cf. A350674.

Programs

  • PARI
    See Links section.

Formula

T(n, k) = T(k, n).
T(n, n) = n.
T(n, 0) = T(0, k) = 0.

A350698 Consider the positive squares summing to n as obtained by the greedy algorithm; a(n) is the least of these squares.

Original entry on oeis.org

1, 1, 1, 4, 1, 1, 1, 4, 9, 1, 1, 1, 4, 1, 1, 16, 1, 1, 1, 4, 1, 1, 1, 4, 25, 1, 1, 1, 4, 1, 1, 1, 4, 9, 1, 36, 1, 1, 1, 4, 1, 1, 1, 4, 9, 1, 1, 1, 49, 1, 1, 1, 4, 1, 1, 1, 4, 9, 1, 1, 1, 4, 1, 64, 1, 1, 1, 4, 1, 1, 1, 4, 9, 1, 1, 1, 4, 1, 1, 16, 81, 1, 1, 1
Offset: 1

Views

Author

Rémy Sigrist, Jan 12 2022

Keywords

Examples

			For n = 13:
- 13 = 3^2 + 2^2,
- so a(13) = 2^2.
		

Crossrefs

Programs

  • PARI
    a(n, e=2) = { my (r=0); while (n, r=sqrtnint(n, e); n-=r^e); r^e }

Formula

a(n^2) = n^2.
a(n) = A350674(n, A053610(n)).
Showing 1-2 of 2 results.