The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A025457 Number of partitions of n into 4 positive cubes. 8
 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,220 COMMENTS The first term > 1 is a(219) = 2. - Michel Marcus, Apr 23 2019 LINKS Robert Israel, Table of n, a(n) for n = 0..10000 FORMULA a(n) = [x^n y^4] Product_{k>=1} 1/(1 - y*x^(k^3)). - Ilya Gutkovskiy, Apr 23 2019 MAPLE N:= 100; A:= Array(0..N); for a from 1 to floor(N^(1/3)) do   for b from a to floor((N-a^3)^(1/3)) do      for c from b to floor((N-a^3-b^3)^(1/3)) do         for d from c to floor((N-a^3-b^3-c^3)^(1/3)) do           n:= a^3 + b^3 + c^3 + d^3;           A[n]:= A[n]+1; od od od od: seq(A[n], n=0..N); # Robert Israel, Aug 18 2014 A025457 := proc(n)     local a, x, y, z, ucu ;     a := 0 ;     for x from 1 do         if 4*x^3 > n then             return a;         end if;         for y from x do             if x^3+3*y^3 > n then                 break;             end if;             for z from y do                 if x^3+y^3+2*z^3 > n then                     break;                 end if;                 ucu := n-x^3-y^3-z^3 ;                 if isA000578(ucu) then                     a := a+1 ;                 end if;             end do:         end do:     end do: end proc: # R. J. Mathar, Sep 15 2015 MATHEMATICA r[n_] := Reduce[0 < a <= b <= c <= d && n == a^3+b^3+c^3+d^3, {a, b, c, d}, Integers]; a[n_] := Which[rn = r[n]; rn === False, 0, rn[[0]] === And, 1, rn[[0]] === Or, Length[rn], True, Print["error ", rn]]; Table[a[n], {n, 0, 107}] (* Jean-François Alcover, Feb 26 2019 *) CROSSREFS Cf. A003108, A025455, A025456, A025403-A025407, A003327, A025420 (greedy inverse). Sequence in context: A023971 A330551 A079260 * A219463 A286688 A285125 Adjacent sequences:  A025454 A025455 A025456 * A025458 A025459 A025460 KEYWORD nonn AUTHOR EXTENSIONS Second offset from Michel Marcus, Apr 23 2019 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified March 28 15:10 EDT 2020. Contains 333089 sequences. (Running on oeis4.)