A024974 -id:A024974 - cp's OEIS frontend

A025469 Number of partitions of n into 3 distinct positive cubes.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0

Offset: 0

David W. Wilson

nonn

In other words, number of solutions to the equation n = x^3 + y^3 + z^3 with x > y > z > 0. - Antti Karttunen, Aug 29 2017

			From _Antti Karttunen_, Aug 29 2017: (Start)
For n = 36 there is one solution: 36 = 27 + 8 + 1, thus a(36) = 1.
For n = 1009 there are two solutions: 1009 = 10^3 + 2^3 + 1^3 = 9^3 + 6^3 + 4^3, thus a(1009) = 2. This is also the first point where sequence attains value greater than one.
(End)

Antti Karttunen, Table of n, a(n) for n = 0..17073
Index entries for sequences related to sums of cubes

Cf. A025465 (not necessarily distinct), A025468, A025419 (greedy inverse).

Cf. A024975 (positions of nonzero terms), A024974 (positions of terms > 1), A025399-A025402.

A025469 := proc(n)
    local a, x, y, zcu ;
    a := 0 ;
    for x from 1 do
        if 3*x^3 > n then
            return a;
        end if;
        for y from x+1 do
            if x^3+2*y^3 > n then
                break;
            end if;
            zcu := n-x^3-y^3 ;
            if zcu > y^3 and isA000578(zcu) then
                a := a+1 ;
            end if;
        end do:
    end do:
end proc:
seq(A025469(n),n=1..80) ; # R. J. Mathar, Jun 15 2018

Table[Count[IntegerPartitions[n, {3}], ?(And[UnsameQ @@ #, AllTrue[#, IntegerQ[#^(1/3)] &]] &)], {n, 105}] (* _Michael De Vlieger, Aug 29 2017 *)

A025469(n) = { my(s=0); for(x=1,n,if(ispower(x,3),for(y=x+1,n-x,if(ispower(y,3),for(z=y+1,n-(x+y),if((ispower(z,3)&&(x+y+z)==n),s++)))))); (s); }; \\ Antti Karttunen, Aug 29 2017

a(n) = A025465(n) - A025468(n). - Antti Karttunen, Aug 29 2017

A025396 Numbers that are the sum of 3 positive cubes in exactly 2 ways.

Original entry on oeis.org

251, 1009, 1366, 1457, 1459, 1520, 1730, 1737, 1756, 1763, 1793, 1854, 1945, 2008, 2072, 2241, 2414, 2456, 2458, 2729, 2736, 3060, 3391, 3457, 3592, 3599, 3655, 3745, 3926, 4105, 4112, 4131, 4168, 4229, 4320, 4376, 4402, 4437, 4447, 4473, 4528, 4616

Offset: 1

David W. Wilson

nonn

Subset of A008917; A025397 gives examples of numbers which are in A008917 but not here. - R. J. Mathar, May 28 2008
A025456(a(n)) = 2. - Reinhard Zumkeller, Apr 23 2009
Superset of A024974 . - Christian N. K. Anderson, Apr 11 2013

			a(1) = 251 = 1^3+5^3+5^3 = 2^3+3^3+6^3. - _Christian N. K. Anderson_, Apr 11 2013

Christian N. K. Anderson, Table of n, a(n) for n = 1..10000
Christian N. K. Anderson, Decomposition of the first 10000 terms into the sets of three cubes

Cf. A008917, A025322, A025395, A025397, A025404, A343708, A344192.

Select[Range[5000], Length[DeleteCases[PowersRepresentations[#,3,3], ?(MemberQ[#,0]&)]] == 2&] (* _Harvey P. Dale, Jan 18 2012 *)

is(n)=k=ceil((n-2)^(1/3)); d=0; for(a=1,k,for(b=a,k,for(c=b,k,if(a^3+b^3+c^3==n,d++))));d
n=3;while(n<5000,if(is(n)==2,print1(n,", "));n++) \\ Derek Orr, Aug 27 2015

A025399 Numbers that are the sum of 3 distinct positive cubes in exactly 1 way.

Original entry on oeis.org

36, 73, 92, 99, 134, 153, 160, 190, 197, 216, 225, 244, 251, 281, 288, 307, 342, 349, 352, 368, 371, 378, 405, 408, 415, 434, 469, 476, 495, 521, 532, 540, 547, 560, 567, 577, 584, 586, 603, 623, 638, 645, 664, 684, 701, 729, 736, 738, 755, 757, 764, 792, 794, 801, 820

Offset: 1

David W. Wilson

nonn

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Cf. A025395 (not necessarily distinct), A024973.

Reap[For[n = 1, n <= 1000, n++, pr = Select[ PowersRepresentations[n, 3, 3], Times @@ # != 0 && Length[#] == Length[Union[#]] &]; If[pr != {} && Length[pr] == 1, Print[n, pr]; Sow[n]]]][[2, 1]] (* Jean-François Alcover, Jul 31 2013 *)

A024975 MINUS A024974. - R. J. Mathar, May 28 2008

{n: A025469(n) = 1}. - R. J. Mathar, Jun 15 2018

A180088 Primes which are the sum of three distinct positive cubes in two or more distinct ways.

Original entry on oeis.org

1009, 4229, 4447, 4733, 6301, 7561, 10657, 12377, 12979, 13103, 13859, 14561, 15569, 15667, 17207, 20663, 20747, 20899, 21673, 22511, 24137, 24499, 25999, 27793, 27917, 28001, 28493, 28729, 29917, 31123, 32579, 32833, 32957, 33119

Offset: 1

Vladimir Joseph Stephan Orlovsky, Aug 09 2010

nonn

1^3+2^3+10^3=1009=4^3+6^3+9^3

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Cf. A011541, A024974, A025400, A122723

lst1=Sort@Select[Flatten[Table[a^3+b^3+c^3,{a,1,66},{b,a-1,1,-1},{c,b-1,1,-1}]],PrimeQ[ # ]&]; lst={};Do[If[lst1[[n]]==lst1[[n+1]],AppendTo[lst,lst1[[n]]]],{n,Length[lst1]-1}];lst

A180089 Semiprimes which are the sum of three distinct positive cubes in two or more distinct ways.

Original entry on oeis.org

1366, 1457, 1793, 1945, 3599, 4105, 5435, 7379, 8315, 9017, 10261, 10963, 11773, 12706, 13957, 15163, 15371, 15553, 15751, 15758, 16271, 17263, 17354, 17947, 18649, 19027, 19369, 19657, 19729, 19774, 19781, 19907, 21026, 21167, 22411

Offset: 1

Vladimir Joseph Stephan Orlovsky, Aug 09 2010

nonn

2^3+3^3+11^3=5^3+8^3+9^3=1366=2*683, 1^3+5^3+11^3=6^3+8^3+9^3=1457=31*47,..

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Cf. A011541, A024974, A025400, A122723, A180088

f[n_]:=Last/@FactorInteger[n]=={1,1}; lst={};Do[Do[Do[If[f[p=a^3+b^3+c^3],AppendTo[lst,p]],{c,b-1,1,-1}],{b,a-1,1,-1}],{a,55}];lst1=Sort@lst; lst={};Do[If[lst1[[n]]==lst1[[n+1]],AppendTo[lst,lst1[[n]]]],{n,Length[lst1]-1}];lst

A180099 Primes which are the sum of three distinct positive cubes of prime numbers in two or more distinct ways.

Original entry on oeis.org

185527, 451837, 591751, 1265471, 1266929, 1618973, 1626227, 1664713, 2586277, 2754683, 2765519, 2805193, 3422303, 3740309, 3748499, 4154779, 5336479, 5483953, 5557987, 6130151, 6586091, 7231013, 7361801, 7726571, 8205553

Offset: 1

Vladimir Joseph Stephan Orlovsky, Aug 09 2010

nonn

			185527 = 47^3+43^3+13^3=53^3+31^3+19^3.

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Cf. A011541, A024974, A025400, A122723, A180088, A180089.

lst={};Do[Do[Do[If[PrimeQ[p=Prime[a]^3+Prime[b]^3+Prime[c]^3],AppendTo[lst,p]],{c,b-1,1,-1}],{b,a-1,1,-1}],{a,88}];lst1=Sort@lst; lst={};Do[If[lst1[[n]]==lst1[[n+1]],AppendTo[lst,lst1[[n]]]],{n,Length[lst1]-1}];lst
Select[Tally[Select[Total/@Subsets[Prime[Range[50]]^3,{3}],PrimeQ]],#[[2]]> 1&] [[All,1]]//Sort (* Harvey P. Dale, Sep 26 2020 *)

A180106 Semiprimes which are the sum of three distinct positive cubes of semiprime numbers in two or more distinct ways.

Original entry on oeis.org

88073, 195905, 196057, 196841, 205102, 211466, 610903, 747209, 809966, 1078622, 1543267, 1828441, 1967402, 2143783, 2312029, 2803501, 3055258, 3108673, 3244466, 3477629, 3662567, 4237577, 4770137, 5741074, 5835593, 5908889, 7189265, 7497118, 8438249, 8742781

Offset: 1

Vladimir Joseph Stephan Orlovsky, Aug 10 2010

nonn

610903 = 74^3+55^3+34^3 = 82^3+39^3+6^3.

88073 = 29*3037 = 21^3+33^3+35^3 = 25^3+26^3+38^3. - Chai Wah Wu, May 20 2017

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Cf. A011541, A024974, A025400, A122723, A180088, A180089, A180099

f[n_] := PrimeOmega@ n == 2; lst = {}; Do[Do[Do[If[And[f[a], f[b], f[c], f[p = a^3 + b^3 + c^3]], AppendTo[lst, p]], {c, b - 1, 1, -1}], {b, a - 1, 1, -1}], {a, 200}]; lst1 = Sort@ lst; lst = {}; Do[If[lst1[[n]] == lst1[[n + 1]], AppendTo[lst, lst1[[n]]]], {n, Length[lst1] - 1}]; lst (* Corrected by Michael De Vlieger, May 21 2017 *)

Terms corrected by Chai Wah Wu, May 20 2017

A219329 Numbers that can be expressed as the sum of three nonnegative cubes in three ways.

Original entry on oeis.org

5104, 5832, 9288, 9729, 10261, 10773, 12104, 12221, 12384, 14175, 17604, 17928, 19034, 20691, 21412, 21888, 24416, 24480, 28792, 29457, 30528, 31221, 32850, 34497, 35216, 36288, 38259, 39339, 39376, 39528, 40060, 40097, 40832, 40851, 41033, 41040, 41364

Offset: 1

Kevin L. Schwartz and Christian N. K. Anderson, Apr 11 2013

nonn

Index of A051343 = 9, superset of index of A025456 = 3.

Subset of A001239.

			a(1) = 5104 = 1^3+12^3+15^3 = 2^3+10^3+16^3 = 9^3+10^3+15^3.

Christian N. K. Anderson, Table of n, a(n) for n = 1..10000
Christian N. K. Anderson, Decomposition of the first 10000 terms into 3 sets of cube triples
Sequences related to sums of squares and cubes

Other sums of cubes: A025402, A025398, A024974, A001239, A008917.
Cf. A025456, A051343.
Cf. A025396.

Select[Range[42000],Length[PowersRepresentations[#,3,3]]==3&] (* Harvey P. Dale, Sep 28 2016 *)

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A025469 Number of partitions of n into 3 distinct positive cubes.

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A025396 Numbers that are the sum of 3 positive cubes in exactly 2 ways.

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A025399 Numbers that are the sum of 3 distinct positive cubes in exactly 1 way.

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A180088 Primes which are the sum of three distinct positive cubes in two or more distinct ways.

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A180089 Semiprimes which are the sum of three distinct positive cubes in two or more distinct ways.

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A180099 Primes which are the sum of three distinct positive cubes of prime numbers in two or more distinct ways.

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A180106 Semiprimes which are the sum of three distinct positive cubes of semiprime numbers in two or more distinct ways.

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A219329 Numbers that can be expressed as the sum of three nonnegative cubes in three ways.

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