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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A326637 Sum of the largest parts of the partitions of n into 10 squarefree parts.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 5, 5, 13, 19, 34, 40, 60, 82, 126, 153, 219, 275, 385, 464, 621, 738, 996, 1168, 1514, 1780, 2287, 2643, 3302, 3839, 4743, 5456, 6638, 7605, 9225, 10479, 12512, 14199, 16929, 19061, 22453, 25300, 29690, 33283, 38715, 43333
Offset: 0

Views

Author

Wesley Ivan Hurt, Jul 14 2019

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Sum[Sum[Sum[Sum[Sum[Sum[Sum[Sum[Sum[(n-i-j-k-l-m-o-p-q-r) * MoebiusMu[r]^2 * MoebiusMu[q]^2 * MoebiusMu[p]^2 * MoebiusMu[o]^2 * MoebiusMu[m]^2 * MoebiusMu[l]^2 * MoebiusMu[k]^2 * MoebiusMu[j]^2 * MoebiusMu[i]^2 * MoebiusMu[n - i - j - k - l - m - o - p - q - r]^2 , {i, j, Floor[(n - j - k - l - m - o - p - q - r)/2]}], {j, k, Floor[(n - k - l - m - o - p - q - r)/3]}], {k, l, Floor[(n - l - m - o - p - q - r)/4]}], {l, m, Floor[(n - m - o - p - q - r)/5]}], {m, o, Floor[(n - o - p - q - r)/6]}], {o, p, Floor[(n - p - q - r)/7]}], {p, q, Floor[(n - q - r)/8]}], {q, r, Floor[(n - r)/9]}], {r, Floor[n/10]}], {n, 0, 50}]

Formula

a(n) = Sum_{r=1..floor(n/10)} Sum_{q=r..floor((n-r)/9)} Sum_{p=q..floor((n-q-r)/8)} Sum_{o=p..floor((n-p-q-r)/7)} Sum_{m=o..floor((n-o-p-q-r)/6)} Sum_{l=m..floor((n-m-o-p-q-r)/5)} Sum_{k=l..floor((n-l-m-o-p-q-r)/4)} Sum_{j=k..floor((n-k-l-m-o-p-q-r)/3)} Sum_{i=j..floor((n-j-k-l-m-o-p-q-r)/2)} mu(r)^2 * mu(q)^2 * mu(p)^2 * mu(o)^2 * mu(m)^2 * mu(l)^2 * mu(k)^2 * mu(j)^2 * mu(i)^2 * mu(n-i-j-k-l-m-o-p-q-r)^2 * (n-i-j-k-l-m-o-p-q-r), where mu is the Möbius function (A008683).
a(n) = A326627(n) - A326628(n) - A326629(n) - A326630(n) - A326631(n) - A326632(n) - A326633(n) - A326634(n) - A326635(n) - A326636(n).

A341070 Number of ways to write n as an ordered sum of 10 squarefree numbers.

Original entry on oeis.org

1, 10, 55, 210, 625, 1552, 3400, 6840, 12960, 23330, 40028, 65740, 104230, 160670, 241640, 354772, 509620, 718980, 999645, 1370720, 1853903, 2476250, 3274110, 4289810, 5568820, 7162184, 9138045, 11579180, 14574755, 18215900, 22619016, 27929990, 34311845, 41921710, 50946945
Offset: 10

Views

Author

Ilya Gutkovskiy, Feb 04 2021

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n, t) option remember;
          `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
          `if`(numtheory[issqrfree](j), b(n-j, t-1), 0), j=1..n)))
        end:
    a:= n-> b(n, 10):
    seq(a(n), n=10..44);  # Alois P. Heinz, Feb 04 2021
  • Mathematica
    nmax = 44; CoefficientList[Series[Sum[MoebiusMu[k]^2 x^k, {k, 1, nmax}]^10, {x, 0, nmax}], x] // Drop[#, 10] &

Formula

G.f.: (Sum_{k>=1} mu(k)^2 * x^k)^10.

A341098 Number of partitions of n into 10 distinct squarefree parts.

Original entry on oeis.org

1, 1, 1, 1, 2, 3, 2, 4, 6, 8, 7, 10, 14, 17, 17, 22, 32, 35, 37, 47, 62, 71, 72, 91, 114, 132, 136, 167, 205, 234, 247, 293, 355, 398, 426, 497, 590, 661, 708, 819, 956, 1066, 1141, 1306, 1501, 1672, 1791, 2030, 2318, 2559, 2747, 3081, 3490, 3835, 4115
Offset: 72

Views

Author

Ilya Gutkovskiy, Feb 04 2021

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n, i, t) option remember; `if`(n=0,
          `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
          `if`(numtheory[issqrfree](i), b(n-i, min(n-i, i-1), t-1), 0)))
        end:
    a:= n-> b(n$2, 10):
    seq(a(n), n=72..126);  # Alois P. Heinz, Feb 04 2021
  • Mathematica
    b[n_, i_, t_] := b[n, i, t] = If[n == 0,
         If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
         If[SquareFreeQ[i], b[n - i, Min[n - i, i - 1], t - 1], 0]]];
    a[n_] := b[n, n, 10];
    Table[a[n], {n, 72, 126}] (* Jean-François Alcover, Feb 24 2022, after Alois P. Heinz *)
Previous Showing 11-13 of 13 results.