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.

Showing 1-10 of 60 results. Next

A254647 Fourth partial sums of eighth powers (A001016).

Original entry on oeis.org

1, 260, 7595, 94360, 723534, 4037712, 17944290, 67127880, 219319815, 642251428, 1718012933, 4258676240, 9892043980, 21721707840, 45414150132, 90930820464, 175208925885, 326205634020, 588861675535, 1033717781096, 1769137540730, 2958360418000, 4842936861750, 7774492635000
Offset: 1

Views

Author

Luciano Ancora, Feb 05 2015

Keywords

Examples

			The eighth powers:   1, 256, 6561, 65536, 390625, ... (A001016)
First partial sums:  1, 257, 6818, 72354, 462979, ... (A000542)
Second partial sums: 1, 258, 7076, 79430, 542409, ... (A253636)
Third partial sums:  1, 259, 7335, 86765, 629174, ... (A254642)
Fourth partial sums: 1, 260, 7595, 94360, 723534, ... (this sequence)
		

Crossrefs

Programs

  • GAP
    List([1..30], n-> Binomial(n+4,5)*(n+2)*((n+2)^2-3)*(2*(n+2)^4 -28*(n+2)^2 +101)/198); # G. C. Greubel, Aug 28 2019
  • Magma
    [Binomial(n+4,5)*(n+2)*((n+2)^2-3)*(2*(n+2)^4 -28*(n+2)^2 +101)/198: n in [1..30]]; // G. C. Greubel, Aug 28 2019
    
  • Maple
    seq(binomial(n+4,5)*(n+2)*((n+2)^2-3)*(2*(n+2)^4 -28*(n+2)^2 +101)/198, n=1..30); # G. C. Greubel, Aug 28 2019
  • Mathematica
    Table[n(1+n)(2+n)^2(3+n)(4+n)(1+4n+n^2)(21 -48n +20n^2 +16n^3 +2n^4 )/23760, {n,20}] (* or *)
    Accumulate[Accumulate[Accumulate[Accumulate[Range[20]^8]]]] (* or *)
    CoefficientList[Series[(1 +247x +4293x^2 +15619x^3 +15619x^4 +4293x^5 + 247x^6 +x^7)/(1-x)^13, {x,0,19}], x]
  • PARI
    a(n)=n*(1+n)*(2+n)^2*(3+n)*(4+n)*(1+4*n+n^2)*(21-48*n+20*n^2 +16*n^3+2*n^4)/23760 \\ Charles R Greathouse IV, Sep 08 2015
    
  • PARI
    vector(30, n, m=n+2; binomial(m+2,5)*m*(m^2-3)*(2*m^4-28*m^2 +101)/198)
    
  • Sage
    [binomial(n+4,5)*(n+2)*((n+2)^2-3)*(2*(n+2)^4 -28*(n+2)^2 +101)/198 for n in (1..30)] # G. C. Greubel, Aug 28 2019
    

Formula

G.f.: x*(1 +247*x +4293*x^2 +15619*x^3 +15619*x^4 +4293*x^5 +247*x^6 +x^7)/(1-x)^13.
a(n) = n*(1+n)*(2+n)^2*(3+n)*(4+n)*(1 +4*n +n^2)*(21 -48*n +20*n^2 + 16*n^3 +2*n^4)/23760.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) + n^8.

A253636 Second partial sums of eighth powers (A001016).

Original entry on oeis.org

1, 258, 7076, 79430, 542409, 2685004, 10592400, 35277012, 103008345, 270739678, 652829892, 1464901802, 3092704433, 6196296120, 11862778432, 21824228040, 38761435089, 66718602714, 111659333380, 182200064046, 290563654073, 453803117636, 695353566480, 1046979329500
Offset: 1

Views

Author

Luciano Ancora, Jan 07 2015

Keywords

Comments

The general formula for the second partial sums of m-th powers is: b(n,m) = (n+1)*F(m)-F(m+1), where F(m) are the m-th Faulhaber’s formulas.

Crossrefs

Programs

  • GAP
    List([1..30], n-> n*(n+1)^2*(n+2)*(2*n^6 +12*n^5 +17*n^4 -12*n^3 -19*n^2 +18*n -3)/180); # G. C. Greubel, Aug 28 2019
  • Magma
    [n*(n+1)^2*(n+2)*(2*n^6+12*n^5+17*n^4-12*n^3-19*n^2+18*n-3)/180: n in [1..25]]; // Bruno Berselli, Jan 08 2015
    
  • Maple
    seq(n*(n+1)^2*(n+2)*(2*n^6 +12*n^5 +17*n^4 -12*n^3 -19*n^2 +18*n -3))/180, n=1..30); # G. C. Greubel, Aug 28 2019
  • Mathematica
    Table[n(n+1)^2(n+2)(2n^6 +12n^5 +17n^4 -12n^3 -19n^2 +18n -3)/180, {n,30}] (* Bruno Berselli, Jan 08 2015 *)
    Nest[Accumulate,Range[30]^8,2] (* or *) LinearRecurrence[{11,-55,165,-330,462,-462,330,-165,55,-11,1},{1,258,7076,79430,542409,2685004,10592400, 35277012, 103008345,270739678,652829892},30] (* Harvey P. Dale, Jul 02 2017 *)
  • PARI
    a(n)=(2*n^10+20*n^9+75*n^8+120*n^7+42*n^6-84*n^5-50*n^4+40*n^3+21*n^2-6*n)/180 \\ Charles R Greathouse IV, Sep 08 2015
    
  • Sage
    [(2*n^10+20*n^9+75*n^8+120*n^7+42*n^6-84*n^5-50*n^4+40*n^3+21*n^2-6*n)/180 for n in [1..24]] # Tom Edgar, Jan 07 2015
    

Formula

a(n) = (2*n^10 + 20*n^9 + 75*n^8 + 120*n^7 + 42*n^6 - 84*n^5 - 50*n^4 + 40*n^3 + 21*n^2 - 6*n)/180.
a(n) = 2*a(n-1) - a(n-2) + n^8. - Robert Israel, Jan 07 2015
G.f.: x*(1 + x)*(1 + 246*x + 4047*x^2 + 11572*x^3 + 4047*x^4 + 246*x^5 + x^6) / (1 - x)^11. - Bruno Berselli, Jan 08 2015

A254642 Third partial sums of eighth powers (A001016).

Original entry on oeis.org

1, 259, 7335, 86765, 629174, 3314178, 13906578, 49183590, 152191935, 422931613, 1075761505, 2540663307, 5633367740, 11829663860, 23692442292, 45516670332, 84278105421, 150996708135, 262656041515, 444856105561, 735419759634, 1189222877270
Offset: 1

Views

Author

Luciano Ancora, Feb 05 2015

Keywords

Examples

			First differences:   1, 255, 6305, 58975, 325089, ...(A022524)
--------------------------------------------------------------------
The eighth powers:   1, 256, 6561, 65536, 390625, ...(A001016)
--------------------------------------------------------------------
First partial sums:  1, 257, 6818, 72354, 462979, ...(A000542)
Second partial sums: 1, 258, 7076, 79430, 542409, ...(A253636)
Third partial sums:  1, 259, 7335, 86765, 629174, ...(this sequence)
		

Crossrefs

Programs

  • Mathematica
    Table[n (1 + n) (2 + n) (3 + n) (3 + 2 n) (1 + 36 n - 69 n^2 + 45 n^4 + 18 n^5 + 2 n^6)/3960, {n, 22}]
    Accumulate[Accumulate[Accumulate[Range[22]^8]]]
    CoefficientList[Series[(1 + 247 x + 4293 x^2 + 15619 x^3 + 15619 x^4 + 4293 x^5 + 247 x^6 + x^7)/(- 1 + x)^12, {x, 0, 22}], x]
  • PARI
    a(n)=n*(1+n)*(2+n)*(3+n)*(3+2*n)*(1+36*n-69*n^2+45*n^4+18*n^5+2*n^6)/3960 \\ Charles R Greathouse IV, Oct 07 2015

Formula

G.f.: (x + 247*x^2 + 4293*x^3 + 15619*x^4 + 15619*x^5 + 4293*x^6 + 247*x^7 + x^8)/(- 1 + x)^12.
a(n) = n*(1 + n)*(2 + n)*(3 + n)*(3 + 2*n)*(1 + 36*n - 69*n^2 + 45*n^4 + 18*n^5 + 2*n^6)/3960.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + n^8.

A255178 Second differences of eighth powers (A001016).

Original entry on oeis.org

1, 254, 6050, 52670, 266114, 963902, 2796194, 6927230, 15257090, 30683774, 57405602, 101263934, 170126210, 274309310, 427043234, 644975102, 948713474, 1363412990, 1919399330, 2652834494, 3606422402, 4830154814, 6382097570, 8329217150, 10748247554
Offset: 0

Views

Author

Luciano Ancora, Feb 21 2015

Keywords

Examples

			Second differences:  1, 254, 6050, 52670, 266114, ... (this sequence)
First differences:   1, 255, 6305, 58975, 325089, ... (A022524)
----------------------------------------------------------------------
The eighth powers:   1, 256, 6561, 65536, 390625, ... (A001016)
----------------------------------------------------------------------
First partial sums:  1, 257, 6818, 72354, 462979, ... (A000542)
Second partial sums: 1, 258, 7076, 79430, 542409, ... (A253636)
Third partial sums:  1, 259, 7335, 86765, 629174, ... (A254642)
Fourth partial sums: 1, 260, 7595, 94360, 723534, ... (A254647)
		

Crossrefs

Programs

  • Magma
    [n eq 0 select 1 else 2*(28*n^6+70*n^4+28*n^2+1): n in [0..30]]; // Vincenzo Librandi, Mar 12 2015
  • Mathematica
    Join[{1}, Table[2 (28 n^6 + 70 n^4 + 28 n^2 + 1), {n, 1, 30}]]
    Join[{1},Differences[Range[0,30]^8,2]] (* Harvey P. Dale, Aug 26 2024 *)

Formula

G.f.: (1 + x)*(1 + 246*x + 4047*x^2 + 11572*x^3 + 4047*x^4 + 246*x^5 + x^6)/(1 - x)^7.
a(n) = 2*(28*n^6 + 70*n^4 + 28*n^2 + 1) for n>0, a(0)=1.

Extensions

Edited by Bruno Berselli, Mar 19 2015

A255182 Third differences of eighth powers (A001016).

Original entry on oeis.org

1, 253, 5796, 46620, 213444, 697788, 1832292, 4131036, 8329860, 15426684, 26721828, 43858332, 68862276, 104183100, 152733924, 217931868, 303738372, 414699516, 555986340, 733435164, 953587908, 1223732412, 1551942756, 1947119580, 2419030404, 2978349948
Offset: 0

Views

Author

Luciano Ancora, Mar 18 2015

Keywords

Examples

			Third differences:   1, 253, 5796, 46620, 213444, ...  (this sequence)
Second differences:  1, 254, 6050, 52670, 266114, ...  (A255178)
First differences:   1, 255, 6305, 58975, 325089, ...  (A022524)
---------------------------------------------------------------------
The seventh powers:  1, 253, 5796, 46620, 213444, ...  (A001016)
---------------------------------------------------------------------
		

Crossrefs

Programs

  • Magma
    [1,253] cat [84*(2*n-1)*(2*n^4-4*n^3+8*n^2-6*n+3): n in [2..30]]; // Vincenzo Librandi, Mar 18 2015
  • Mathematica
    Join[{1, 253}, Table[84 (2 n - 1) (2 n^4 - 4 n^3 + 8 n^2 - 6 n + 3), {n, 2, 30}]]

Formula

G.f.: (1 + 247*x + 4293*x^2 + 15619*x^3 + 15619*x^4 + 4293*x^5 + 247*x^6 + x^7)/(1 - x)^6.
a(n) = 84*(2*n - 1)*(2*n^4 - 4*n^3 + 8*n^2 - 6*n + 3) for n>1, a(0)=1, a(1)=253.

Extensions

Edited by Bruno Berselli, Mar 19 2015

A279641 Exponential transform of the eighth powers A001016.

Original entry on oeis.org

1, 1, 257, 7330, 289925, 18565676, 1042651237, 69221777920, 5270005429705, 415374654294352, 35626036180630121, 3293064510986584544, 320276195119275204493, 32969303384902657225792, 3579970600334581051222093, 406942001917387287570455296
Offset: 0

Views

Author

Alois P. Heinz, Dec 16 2016

Keywords

Crossrefs

Column k=8 of A279636.
Cf. A001016.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1,
          add(binomial(n-1, j-1)*j^8*a(n-j), j=1..n))
        end:
    seq(a(n), n=0..25);

Formula

E.g.f.: exp(exp(x)*(x^8+28*x^7+266*x^6+1050*x^5+1701*x^4+966*x^3 +127*x^2 +x)).

A003381 Numbers that are the sum of 3 nonzero 8th powers.

Original entry on oeis.org

3, 258, 513, 768, 6563, 6818, 7073, 13123, 13378, 19683, 65538, 65793, 66048, 72098, 72353, 78658, 131073, 131328, 137633, 196608, 390627, 390882, 391137, 397187, 397442, 403747, 456162, 456417, 462722, 521697, 781251, 781506, 787811, 846786
Offset: 1

Views

Author

Keywords

Crossrefs

Cf. A001016 (8th powers).

Programs

  • Maple
    A003381 := proc(nmax::integer)
        local xyzmax, ins, x,x8,y,y8,z,z8 ;
            xyzmax := ceil(root[8](nmax/3)) ;
            a := {} ;
            for x from 1 to xyzmax do
                    x8 := x^8 ;
                    if 3*x8 > nmax then
                            break;
                    end if;
                    for y from x do
                            y8 := y^8 ;
                            if x8+2*y8 > nmax then
                                    break;
                            end if;
                            for z from y do
                                    z8 := z^8 ;
                                    if x8+y8+z8 > nmax then
                                            break;
                                    end if;
                                    if x8+y8+z8 <= nmax then
                                            a := a  union {x8+y8+z8} ;
                                    end if;
                            end do:
                    end do:
            end do:
            sort(convert(a,list)) ;
    end proc:
    nmax := 6755626171875 ;
    L:= A003381(nmax) ;
    LISTTOBFILE(L,"b003381.txt",1) ; # R. J. Mathar, Aug 01 2020
  • Mathematica
    kmax = 4*10^12;
    m = kmax^(1/8) // Ceiling;
    Table[k = x^8 + y^8 + z^8; If[k <= kmax, k, Nothing], {x, 1, m}, {y, x, m}, {z, y, m}] // Flatten // Union (* Jean-François Alcover, May 02 2023 *)

A003389 Numbers that are the sum of 11 positive 8th powers.

Original entry on oeis.org

11, 266, 521, 776, 1031, 1286, 1541, 1796, 2051, 2306, 2561, 2816, 6571, 6826, 7081, 7336, 7591, 7846, 8101, 8356, 8611, 8866, 9121, 13131, 13386, 13641, 13896, 14151, 14406, 14661, 14916, 15171, 15426, 19691, 19946, 20201, 20456, 20711, 20966, 21221, 21476, 21731, 26251
Offset: 1

Views

Author

Keywords

Examples

			From _David A. Corneth_, Aug 03 2020: (Start)
2488200 is in the sequence as 2488200 = 2^8 + 3^8 + 3^8 + 4^8 + 4^8 + 5^8 + 5^8 + 5^8 + 5^8 + 5^8 + 5^8.
3418281 is in the sequence as 3418281 = 3^8 + 3^8 + 3^8 + 3^8 + 3^8 + 3^8 + 3^8 + 3^8 + 3^8 + 6^8 + 6^8.
5249412 is in the sequence as 5249412 = 4^8 + 4^8 + 4^8 + 4^8 + 4^8 + 5^8 + 5^8 + 5^8 + 5^8 + 6^8 + 6^8. (End)
		

Crossrefs

Subsequence of A004884.
Cf. A001016 (eighth powers).

Formula

a(n) > 8n/3. (Work mod 32.) - Charles R Greathouse IV, May 04 2015

A003382 Numbers that are the sum of 4 nonzero 8th powers.

Original entry on oeis.org

4, 259, 514, 769, 1024, 6564, 6819, 7074, 7329, 13124, 13379, 13634, 19684, 19939, 26244, 65539, 65794, 66049, 66304, 72099, 72354, 72609, 78659, 78914, 85219, 131074, 131329, 131584, 137634, 137889, 144194, 196609, 196864, 203169, 262144
Offset: 1

Views

Author

Keywords

Comments

As the order of addition doesn't matter we can assume terms are in nondecreasing order. - David A. Corneth, Aug 01 2020

Examples

			From _David A. Corneth_, Aug 01 2020: (Start)
1246103043 is in the sequence as 1246103043 = 1^8 + 5^8 + 12^8 + 13^8.
4194358628 is in the sequence as 4194358628 = 3^8 + 13^8 + 13^8 + 15^8.
5148323267 is in the sequence as 5148323267 = 7^8 + 8^8 + 15^8 + 15^8. (End)
		

Crossrefs

Cf. A001016 (8th powers).
A###### (x, y): Numbers that are the form of x nonzero y-th powers.
Cf. A000404 (2, 2), A000408 (3, 2), A000414 (4, 2), A003072 (3, 3), A003325 (3, 2), A003327 (4, 3), A003328 (5, 3), A003329 (6, 3), A003330 (7, 3), A003331 (8, 3), A003332 (9, 3), A003333 (10, 3), A003334 (11, 3), A003335 (12, 3), A003336 (2, 4), A003337 (3, 4), A003338 (4, 4), A003339 (5, 4), A003340 (6, 4), A003341 (7, 4), A003342 (8, 4), A003343 (9, 4), A003344 (10, 4), A003345 (11, 4), A003346 (12, 4), A003347 (2, 5), A003348 (3, 5), A003349 (4, 5), A003350 (5, 5), A003351 (6, 5), A003352 (7, 5), A003353 (8, 5), A003354 (9, 5), A003355 (10, 5), A003356 (11, 5), A003357 (12, 5), A003358 (2, 6), A003359 (3, 6), A003360 (4, 6), A003361 (5, 6), A003362 (6, 6), A003363 (7, 6), A003364 (8, 6), A003365 (9, 6), A003366 (10, 6), A003367 (11, 6), A003368 (12, 6), A003369 (2, 7), A003370 (3, 7), A003371 (4, 7), A003372 (5, 7), A003373 (6, 7), A003374 (7, 7), A003375 (8, 7), A003376 (9, 7), A003377 (10, 7), A003378 (11, 7), A003379 (12, 7), A003380 (2, 8), A003381 (3, 8), A003382 (4, 8), A003383 (5, 8), A003384 (6, 8), A003385 (7, 8), A003387 (9, 8), A003388 (10, 8), A003389 (11, 8), A003390 (12, 8), A003391 (2, 9), A003392 (3, 9), A003393 (4, 9), A003394 (5, 9), A003395 (6, 9), A003396 (7, 9), A003397 (8, 9), A003398 (9, 9), A003399 (10, 9), A004800 (11, 9), A004801 (12, 9), A004802 (2, 10), A004803 (3, 10), A004804 (4, 10), A004805 (5, 10), A004806 (6, 10), A004807 (7, 10), A004808 (8, 10), A004809 (9, 10), A004810 (10, 10), A004811 (11, 10), A004812 (12, 10), A004813 (2, 11), A004814 (3, 11), A004815 (4, 11), A004816 (5, 11), A004817 (6, 11), A004818 (7, 11), A004819 (8, 11), A004820 (9, 11), A004821 (10, 11), A004822 (11, 11), A004823 (12, 11), A047700 (5, 2).

Programs

  • Maple
    A003382 := proc(nmax::integer)
        local a, x,x8,y,y8,z,z8,u,u8 ;
        a := {} ;
        for x from 1 do
            x8 := x^8 ;
            if 4*x8 > nmax then
                break;
            end if;
            for y from x do
                y8 := y^8 ;
                if x8+3*y8 > nmax then
                    break;
                end if;
                for z from y do
                    z8 := z^8 ;
                    if x8+y8+2*z8 > nmax then
                        break;
                    end if;
                    for u from z do
                        u8 := u^8 ;
                        if x8+y8+z8+u8 > nmax then
                            break;
                        end if;
                        if x8+y8+z8+u8 <= nmax then
                            a := a  union {x8+y8+z8+u8} ;
                        end if;
                    end do:
                end do:
            end do:
        end do:
        sort(convert(a,list)) ;
    end proc:
    nmax := 102400000000 ;
    L:= A003382(nmax) ;
    LISTTOBFILE(L,"b003382.txt",1) ; # R. J. Mathar, Aug 01 2020
  • Mathematica
    M = 102400000000;
    m = M^(1/8) // Ceiling;
    Table[s = a^8+b^8+c^8+d^8; If[s>M, Nothing, s], {a, m}, {b, m}, {c, m}, {d, m}] // Flatten // Union (* Jean-François Alcover, Dec 01 2020 *)

Extensions

Incorrect program removed by David A. Corneth, Aug 01 2020

A003383 Numbers that are the sum of 5 nonzero 8th powers.

Original entry on oeis.org

5, 260, 515, 770, 1025, 1280, 6565, 6820, 7075, 7330, 7585, 13125, 13380, 13635, 13890, 19685, 19940, 20195, 26245, 26500, 32805, 65540, 65795, 66050, 66305, 66560, 72100, 72355, 72610, 72865, 78660, 78915, 79170, 85220, 85475, 91780, 131075
Offset: 1

Views

Author

Keywords

Comments

As the order of addition doesn't matter we can assume terms are in nondecreasing order. - David A. Corneth, Aug 01 2020

Examples

			From _David A. Corneth_, Aug 01 2020: (Start)
100131584 is in the sequence as 100131584 = 2^8 + 2^8 + 4^8 + 4^8 + 10^8.
320123684 is in the sequence as 320123684 = 1^8 + 1^8 + 7^8 + 10^8 + 11^8.
750105634 is in the sequence as 750105634 = 2^8 + 7^8 + 10^8 + 11^8 + 12^8. (End)
		

Crossrefs

Cf. A001016 (8th powers).
A###### (x, y): Numbers that are the form of x nonzero y-th powers.
Cf. A000404 (2, 2), A000408 (3, 2), A000414 (4, 2), A003072 (3, 3), A003325 (3, 2), A003327 (4, 3), A003328 (5, 3), A003329 (6, 3), A003330 (7, 3), A003331 (8, 3), A003332 (9, 3), A003333 (10, 3), A003334 (11, 3), A003335 (12, 3), A003336 (2, 4), A003337 (3, 4), A003338 (4, 4), A003339 (5, 4), A003340 (6, 4), A003341 (7, 4), A003342 (8, 4), A003343 (9, 4), A003344 (10, 4), A003345 (11, 4), A003346 (12, 4), A003347 (2, 5), A003348 (3, 5), A003349 (4, 5), A003350 (5, 5), A003351 (6, 5), A003352 (7, 5), A003353 (8, 5), A003354 (9, 5), A003355 (10, 5), A003356 (11, 5), A003357 (12, 5), A003358 (2, 6), A003359 (3, 6), A003360 (4, 6), A003361 (5, 6), A003362 (6, 6), A003363 (7, 6), A003364 (8, 6), A003365 (9, 6), A003366 (10, 6), A003367 (11, 6), A003368 (12, 6), A003369 (2, 7), A003370 (3, 7), A003371 (4, 7), A003372 (5, 7), A003373 (6, 7), A003374 (7, 7), A003375 (8, 7), A003376 (9, 7), A003377 (10, 7), A003378 (11, 7), A003379 (12, 7), A003380 (2, 8), A003381 (3, 8), A003382 (4, 8), A003383 (5, 8), A003384 (6, 8), A003385 (7, 8), A003387 (9, 8), A003388 (10, 8), A003389 (11, 8), A003390 (12, 8), A003391 (2, 9), A003392 (3, 9), A003393 (4, 9), A003394 (5, 9), A003395 (6, 9), A003396 (7, 9), A003397 (8, 9), A003398 (9, 9), A003399 (10, 9), A004800 (11, 9), A004801 (12, 9), A004802 (2, 10), A004803 (3, 10), A004804 (4, 10), A004805 (5, 10), A004806 (6, 10), A004807 (7, 10), A004808 (8, 10), A004809 (9, 10), A004810 (10, 10), A004811 (11, 10), A004812 (12, 10), A004813 (2, 11), A004814 (3, 11), A004815 (4, 11), A004816 (5, 11), A004817 (6, 11), A004818 (7, 11), A004819 (8, 11), A004820 (9, 11), A004821 (10, 11), A004822 (11, 11), A004823 (12, 11), A047700 (5, 2).

Programs

  • Maple
    A003383 := proc(nmax::integer)
        local a, x,x8,y,y8,z,z8,u,u8,v,v8 ;
        a := {} ;
        for x from 1 do
            x8 := x^8 ;
            if 5*x8 > nmax then
                break;
            end if;
            for y from x do
                y8 := y^8 ;
                if x8+4*y8 > nmax then
                    break;
                end if;
                for z from y do
                    z8 := z^8 ;
                    if x8+y8+3*z8 > nmax then
                        break;
                    end if;
                    for u from z do
                        u8 := u^8 ;
                        if x8+y8+z8+2*u8 > nmax then
                            break;
                        end if;
                        for v from u do
                            v8 := v^8 ;
                            if x8+y8+z8+u8+v8 > nmax then
                                break;
                            end if;
                            if x8+y8+z8+u8+v8 <= nmax then
                                a := a  union {x8+y8+z8+u8+v8} ;
                            end if;
                        end do:
                    end do:
                end do:
            end do:
        end do:
        sort(convert(a,list)) ;
    end proc:
    nmax := 500000000 ; ;
    L:= A003383(nmax) ;
    LISTTOBFILE(L,"b003383.txt",1) ; # R. J. Mathar, Aug 01 2020
  • Mathematica
    M = 3784086305;
    m = M^(1/8) // Ceiling;
    Table[s = a^8+b^8+c^8+d^8+e^8; If[s>M, Nothing, s], {a, m}, {b, m}, {c, m}, {d, m}, {e, m}] // Flatten // Union (* Jean-François Alcover, Dec 01 2020 *)
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