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.

Previous Showing 21-30 of 46 results. Next

A001553 a(n) = 1^n + 2^n + ... + 6^n.

Original entry on oeis.org

6, 21, 91, 441, 2275, 12201, 67171, 376761, 2142595, 12313161, 71340451, 415998681, 2438235715, 14350108521, 84740914531, 501790686201, 2978035877635, 17706908038281, 105443761093411, 628709267031321, 3752628871164355, 22418196307542441, 134023513204581091
Offset: 0

Views

Author

Keywords

Comments

For the o.g.f.s of such sequences see the W. Lang link under A196837. The e.g.f.s are trivial. - Wolfdieter Lang, Oct 14 2011
a(n) is divisible by 7 iff n is not divisible by 6 (see De Koninck & Mercier reference). Example: a(5)= 12201 = 7 * 1743 and a(6) = 67171 = 9595 * 7 + 6. - Bernard Schott, Mar 06 2020

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 813.
  • J.-M. De Koninck and A. Mercier, 1001 Problèmes en Théorie Classique des Nombres, Problème 289 pp. 45, 194, Ellipses, Paris, (2004).
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Column 6 of array A103438, A001552.

Programs

  • Mathematica
    Table[Total[Range[6]^n], {n, 0, 40}] (* T. D. Noe, Oct 10 2011 *)

Formula

a(n) = Sum_{k=1..6} k^n.
From Wolfdieter Lang, Oct 10 2011: (Start)
E.g.f.: (1-exp(6*x))/(exp(-x)-1) = Sum_{j=1..6} exp(j*x) (trivial).
O.g.f.: (2 - 7*x)*(3 - 42*x + 203*x^2 - 392*x^3 + 252*x^4)/Product_{j=1..6} (1 - j*x).
From the Laplace transformation of the e.g.f. (with argument 1/p, and multiplied with 1/p), which yields the partial fraction decomposition of the given o.g.f., namely Sum_{j=1..6} 1/(1 - j*x).
(End)

Extensions

More terms from Jon E. Schoenfield, Mar 24 2010

A162298 Faulhaber's triangle: triangle T(k,y) read by rows, giving numerator of the coefficient [m^y] of the polynomial Sum_{x=1..m} x^(k-1).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 0, 1, 1, 1, -1, 0, 1, 1, 1, 0, -1, 0, 5, 1, 1, 1, 0, -1, 0, 1, 1, 1, 0, 1, 0, -7, 0, 7, 1, 1, -1, 0, 2, 0, -7, 0, 2, 1, 1, 0, -3, 0, 1, 0, -7, 0, 3, 1, 1, 5, 0, -1, 0, 1, 0, -1, 0, 5, 1, 1, 0, 5, 0, -11, 0, 11, 0, -11, 0, 11, 1, 1, -691, 0, 5, 0, -33, 0, 22, 0, -11, 0, 1, 1, 1, 0, -691, 0, 65, 0, -143, 0, 143, 0, -143, 0, 13, 1, 1
Offset: 0

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Author

Juri-Stepan Gerasimov, Jun 30 2009 and Jul 02 2009

Keywords

Comments

There are many versions of Faulhaber's triangle: search the OEIS for his name. For example, A220962/A220963 is essentially the same as this triangle, except for an initial column of 0's. - N. J. A. Sloane, Jan 28 2017
Named after the German mathematician Johann Faulhaber (1580-1653). - Amiram Eldar, Jun 13 2021
From Wolfdieter Lang, Oct 23 2011 (Start):
The sums of the k-th power of each of the first n positive integers, sum(j^k,j=1..n), k>=0, n>=1, abbreviated usually as Sigma n^k, can be written as Sigma n^k = sum(r(k,m)*n^m,m=1..k+1), with the rational number triangle r(n,m)=a(n,m)/A162299(k+1,m). See, e.g., the Graham et al. reference, eq. (6.78), p. 269, where Sigma n^k is S_k(n+1) - delta(k,0), with delta(k,0)=1 if k=0 and 0 else. The formula for r(n,m) given below can be adapted from this reference, and it is found in the given form (for k>0) in the Remmert reference, p. 175.
For sums of powers of integers see the array A103438 with further references and links.
(End)

Examples

			The first few polynomials:
    m;
   m/2  + m^2/2;
   m/6  + m^2/2 + m^3/3;
    0   + m^2/4 + m^3/2 + m^4/4;
  -m/30 +   0   + m^3/3 + m^4/2 + m^5/5;
  ...
Initial rows of Faulhaber's triangle of fractions H(n, k) (n >= 0, 1 <= k <= n+1):
    1;
   1/2,  1/2;
   1/6,  1/2,  1/3;
    0,   1/4,  1/2,  1/4;
  -1/30,  0,   1/3,  1/2,  1/5;
    0,  -1/12,  0,   5/12, 1/2,  1/6;
   1/42,  0,  -1/6,   0,   1/2,  1/2,  1/7;
    0,   1/12,  0,  -7/24,  0,   7/12, 1/2,  1/8;
  -1/30,  0,   2/9,   0,  -7/15,  0,   2/3,  1/2,  1/9;
  ...
		

Crossrefs

Cf. A000367, A162299 (denominators), A103438, A196837.
See also A220962/A220963.

Programs

  • Maple
    A162298 := proc(k, y) local gf, x; gf := sum(x^(k-1), x=1..m) ; coeftayl(gf, m=0, y) ; numer(%) ; end proc: # R. J. Mathar, Mar 26 2013
    # To produce Faulhaber's triangle of fractions H(n,k) (n >= 0, 1 <= k <= n+1):
    H:=proc(n,k) option remember; local i;
    if n<0 or k>n+1 then 0;
    elif n=0 then 1;
    elif k>1 then (n/k)*H(n-1,k-1);
    else 1 - add(H(n,i),i=2..n+1); fi; end;
    for n from 0 to 10 do lprint([seq(H(n,k),k=1..n+1)]); od:
    for n from 0 to 12 do lprint([seq(numer(H(n,k)),k=1..n+1)]); od: # A162298
    for n from 0 to 12 do lprint([seq(denom(H(n,k)),k=1..n+1)]); od: # A162299 # N. J. A. Sloane, Jan 28 2017
  • Mathematica
    H[n_, k_] := H[n, k] = Which[n < 0 || k > n+1, 0, n == 0, 1, k > 1, (n/k)* H[n-1, k-1], True, 1 - Sum[H[n, i], {i, 2, n+1}]];
    Table[H[n, k] // Numerator, {n, 0, 13}, {k, 1, n+1}] // Flatten (* Jean-François Alcover, Aug 04 2022 *)

Formula

Faulhaber's triangle of fractions H(n,k) (n >= 0, 1 <= k <= n+1) is defined by: H(0,1)=1; for 2<=k<=n+1, H(n,k) = (n/k)*H(n-1,k-1) with H(n,1) = 1 - Sum_{i=2..n+1}H(n,i). - N. J. A. Sloane, Jan 28 2017
Sum_{x=1..m} x^(k-1) = (Bernoulli(k,m+1)-Bernoulli(k))/k.
T(k,m)= numerator(r(k,m)) with r(k,m)= 1/(k+1) if m=k+1, 1/2 if m=k, and (B(k+1-m)/(k+1-m))*binomial(k,m) if m = 1,...,k-1, with the Bernoulli numbers B(n)=A027641(n)/A027642(n). Alternatively r(k,m) = ((-1)^(k+1-m))*sum(S(k,l)*s(l+1,m)/(l+1),l=(m-1),...,k), k>=0, m=1,...,k+1, with S given in A048993, and s given in A048994. - Wolfdieter Lang, Oct 23 2011

Extensions

Offset set to 0 by Alois P. Heinz, Feb 19 2021

A001554 a(n) = 1^n + 2^n + ... + 7^n.

Original entry on oeis.org

7, 28, 140, 784, 4676, 29008, 184820, 1200304, 7907396, 52666768, 353815700, 2393325424, 16279522916, 111239118928, 762963987380, 5249352196144, 36210966447236, 250337422025488, 1733857359003860, 12027604452404464, 83544895168776356, 580964060390826448
Offset: 0

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Author

Keywords

Comments

Conjectures for o.g.f.s for this type of sequences appear in the PhD thesis by Simon Plouffe. See A001552 for the reference. These conjectures are proved in a link given in A196837. - Wolfdieter Lang, Oct 15 2011

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 813.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Column 7 of array A103438. A196837.

Programs

Formula

From Wolfdieter Lang, Oct 15 2011: (Start)
E.g.f.: (1-exp(7*x))/(exp(-x)-1) = Sum_{j=1..7} exp(j*x) (trivial).
O.g.f.: (7 - 168*x + 1610*x^2 - 7840*x^3 + 20307*x^4 - 26264*x^5 + 13068*x^6)/Product_{j=1..7} (1 - j*x). From the e.g.f. via Laplace transformation. See the proof in a link under A196837. (End)

Extensions

More terms from Jon E. Schoenfield, Mar 24 2010

A057291 Numbers k such that k | 12^k + 11^k + 10^k + 9^k + 8^k + 7^k + 6^k + 5^k + 4^k + 3^k + 2^k + 1^k.

Original entry on oeis.org

1, 2, 3, 9, 10, 13, 26, 27, 39, 50, 81, 110, 117, 130, 169, 243, 250, 279, 310, 338, 351, 470, 507, 550, 650, 663, 729, 1053, 1209, 1250, 1430, 1521, 1550, 1690, 2187, 2197, 2750, 3159, 3250, 3410, 4030, 4043, 4069, 4394, 4509, 4563, 6250, 6561, 6591, 7150
Offset: 1

Views

Author

Robert G. Wilson v, Sep 22 2000

Keywords

Comments

The only primes in the sequence are 2, 3 and 13. - Robert Israel, Jun 25 2025

Crossrefs

Programs

  • Maple
    filter:= n -> 12&^n + 11&^n + 10&^n + 9&^n + 8&^n + 7&^n + 6&^n + 5&^n + 4&^n + 3&^n + 2&^n + 1 mod n = 0:
    select(filter, [$1..10^4]); # Robert Israel, Jun 25 2025
  • Mathematica
    Select[ Range[ 10^5 ], Mod[ PowerMod[ 12, #, # ] + PowerMod[ 11, #, # ] + PowerMod[ 10, #, # ] + PowerMod[ 9, #, # ] + PowerMod[ 8, #, # ] + PowerMod[ 7, #, # ] + PowerMod[ 6, #, # ] + PowerMod[ 5, #, # ] + PowerMod[ 4, #, # ] + PowerMod[ 3, #, # ] + PowerMod[ 2, #, # ] + 1, # ] == 0 & ]
    Select[Range[7200],Divisible[Total[Range[12]^#],#]&] (* Harvey P. Dale, Aug 05 2017 *)

A057292 Numbers k such that k | 11^k + 10^k + 9^k + 8^k + 7^k + 6^k + 5^k + 4^k + 3^k + 2^k + 1^k.

Original entry on oeis.org

1, 2, 3, 9, 11, 22, 27, 33, 46, 81, 99, 121, 209, 242, 243, 297, 363, 729, 891, 1058, 1089, 1179, 1331, 1702, 2187, 2662, 2673, 3082, 3267, 3993, 6561, 8019, 9801, 11979, 14641, 19683, 20673, 24057, 24334, 25029, 29282, 29403, 30591, 30734
Offset: 1

Views

Author

Robert G. Wilson v, Sep 22 2000

Keywords

Comments

The only primes in the sequence are 2, 3 and 11. - Robert Israel, Jun 25 2025

Crossrefs

Programs

  • Maple
    filter:= n ->  11&^n + 10&^n + 9&^n + 8&^n + 7&^n + 6&^n + 5&^n + 4&^n + 3&^n + 2&^n + 1 mod n = 0:
    select(filter, [$1..10^5]); # Robert Israel, Jun 25 2025
  • Mathematica
    Select[ Range[ 10^5 ], Mod[ PowerMod[ 11, #, # ] + PowerMod[ 10, #, # ] + PowerMod[ 9, #, # ] + PowerMod[ 8, #, # ] + PowerMod[ 7, #, # ] + PowerMod[ 6, #, # ] + PowerMod[ 5, #, # ] + PowerMod[ 4, #, # ] + PowerMod[ 3, #, # ] + PowerMod[ 2, #, # ] + 1, # ] == 0 & ]
    Select[Range[31000],Mod[Total[PowerMod[Range[0,11],#,#]],#]==0&] (* Harvey P. Dale, Nov 22 2021 *)

A103439 a(n) = Sum_{i=0..n-1} Sum_{j=0..i} (i-j+1)^j.

Original entry on oeis.org

0, 1, 3, 7, 16, 39, 105, 315, 1048, 3829, 15207, 65071, 297840, 1449755, 7468541, 40555747, 231335960, 1381989881, 8623700811, 56078446615, 379233142800, 2662013133295, 19362917622001, 145719550012299, 1133023004941272, 9090156910550109, 75161929739797519
Offset: 0

Views

Author

Ralf Stephan, Feb 11 2005

Keywords

Comments

Partial sums of A026898.
Antidiagonal sums of array A103438.
Row sums of A123490. - Paul Barry, Oct 01 2006

Crossrefs

Programs

  • Magma
    [0] cat [(&+[ (&+[ (k-j+1)^j : j in [0..k]]) : k in [0..n-1]]): n in [1..30]]; // G. C. Greubel, Jun 15 2021
    
  • Maple
    b:= proc(i) option remember; add((i-j+1)^j, j=0..i) end:
    a:= proc(n) option remember; add(b(i), i=0..n-1) end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Dec 02 2019
  • Mathematica
    Join[{0},Table[Sum[Sum[(i-j+1)^j,{j,0,i}],{i,0,n}],{n,0,30}]] (* Harvey P. Dale, Dec 03 2018 *)
  • PARI
    a(n) = sum(i=0, n-1, sum(j=0, i, (i-j+1)^j)); \\ Michel Marcus, Jun 15 2021
  • Sage
    [sum(sum((k-j+1)^j for j in (0..k)) for k in (0..n-1)) for n in (0..30)] # G. C. Greubel, Jun 15 2021
    

Formula

a(n+1) = Sum_{k=0..n} ((k+2)^(n-k) + k)/(k+1). - Paul Barry, Oct 01 2006
G.f.: (G(0)-1)/(1-x) where G(k) = 1 + x*(2*k*x-1)/(2*k*x+x-1 - x*(2*k*x+x-1)^2/(x*(2*k*x+x-1) + (2*k*x+2*x-1)/G(k+1) )); (recursively defined continued fraction). - Sergei N. Gladkovskii, Jan 26 2013

Extensions

Name edited by Alois P. Heinz, Dec 02 2019

A308477 Square array A(n,k), n >= 1, k >= 0, read by antidiagonals: A(n,k) = Sum_{j=1..n, gcd(n,j) = 1} j^k.

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 5, 4, 4, 1, 1, 9, 10, 10, 2, 1, 1, 17, 28, 30, 6, 6, 1, 1, 33, 82, 100, 26, 21, 4, 1, 1, 65, 244, 354, 126, 91, 16, 6, 1, 1, 129, 730, 1300, 626, 441, 84, 27, 4, 1, 1, 257, 2188, 4890, 3126, 2275, 496, 159, 20, 10, 1, 1, 513, 6562, 18700, 15626, 12201, 3108, 1053, 140, 55, 4
Offset: 1

Views

Author

Ilya Gutkovskiy, May 29 2019

Keywords

Examples

			Square array begins:
  1,   1,   1,    1,    1,     1,  ...
  1,   1,   1,    1,    1,     1,  ...
  2,   3,   5,    9,   17,    33,  ...
  2,   4,  10,   28,   82,   244,  ...
  4,  10,  30,  100,  354,  1300,  ...
  2,   6,  26,  126,  626,  3126,  ...
		

Crossrefs

Columns k=0..4 give A000010, A023896, A053818, A053819, A053820.
Cf. A103438.

Programs

  • Mathematica
    Table[Function[k, Sum[If[GCD[n, j] == 1, j^k, 0], {j, 1, n}]][i - n], {i, 0, 12}, {n, 1, i}] // Flatten

A001555 a(n) = 1^n + 2^n + ... + 8^n.

Original entry on oeis.org

8, 36, 204, 1296, 8772, 61776, 446964, 3297456, 24684612, 186884496, 1427557524, 10983260016, 84998999652, 660994932816, 5161010498484, 40433724284976, 317685943157892, 2502137235710736, 19748255868485844, 156142792528260336, 1236466399775623332
Offset: 0

Views

Author

Keywords

Comments

Conjectures for o.g.f.s for this type of sequence appear in the PhD thesis by Simon Plouffe. See A001552 for the reference. These conjectures are proved in a link given in A196837. [Wolfdieter Lang, Oct 15 2011]

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 813.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Column 8 of array A103438.

Programs

  • Maple
    seq(add(j^n,j=1..8), n=0..20); # Robert Israel, Aug 23 2015
  • Mathematica
    Table[Total[Range[8]^n], {n, 0, 20}] (* T. D. Noe, Aug 09 2012 *)
  • PARI
    first(m)=vector(m,n,n--;sum(i=1,8,i^n)) \\ Anders Hellström, Aug 23 2015

Formula

From Wolfdieter Lang, Oct 15 2011 (Start)
E.g.f.: (1-exp(8*x))/(exp(-x)-1) = Sum_{j=1..8} exp(j*x) (trivial).
O.g.f.: 4*(2-9*x)*(1-27*x+288*x^2-1539*x^3+4299*x^4-5886*x^5+3044*x^6) / Product_{j=1..8} (1-j*x). From the e.g.f. via Laplace transformation. See the proof in a link under A196837. (End)
a(n) = A001554(n) + A001018(n). - Michel Marcus, Jul 26 2013

Extensions

More terms from Jon E. Schoenfield, Mar 24 2010

A001556 a(n) = 1^n + 2^n + ... + 9^n.

Original entry on oeis.org

9, 45, 285, 2025, 15333, 120825, 978405, 8080425, 67731333, 574304985, 4914341925, 42364319625, 367428536133, 3202860761145, 28037802953445, 246324856379625, 2170706132009733, 19179318935377305, 169842891165484965, 1506994510201252425
Offset: 0

Views

Author

Keywords

Comments

Conjectures for o.g.f.s for this type of sequences appear in the PhD thesis by Simon Plouffe. See A001552 for the reference. These conjectures are proved in the link given in A196837. - Wolfdieter Lang, Oct 15 2011

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 813.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Column 9 of array A103438. A196837.

Programs

  • Mathematica
    Table[Total[Range[9]^n], {n, 0, 20}] (* T. D. Noe, Aug 09 2012 *)

Formula

a(n) = sum_{j=1..9} j^n, n>=0.
From Wolfdieter Lang, Oct 15 2011: (Start)
E.g.f.: (1-exp(9*x))/(exp(-x)-1) = sum(exp(j*x),j=1..9) (trivial).
O.g.f.: (9 - 360*x + 6090*x^2 - 56700*x^3 + 316365*x^4 - 1077300*x^5 + 2171040*x^6 - 2345400*x^7 + 1026576*x^8)/product_{j=1..9} (1-j*x).
From the e.g.f. via Laplace transformation. See the proof in a link under A196837.
(End)
a(n) = A001555(n) + A001019(n). - Michel Marcus, Jul 26 2013

Extensions

More terms from Jon E. Schoenfield, Mar 24 2010

A001557 a(n) = 1^n + 2^n + ... + 10^n.

Original entry on oeis.org

10, 55, 385, 3025, 25333, 220825, 1978405, 18080425, 167731333, 1574304985, 14914341925, 142364319625, 1367428536133, 13202860761145, 128037802953445, 1246324856379625, 12170706132009733, 119179318935377305, 1169842891165484965, 11506994510201252425
Offset: 0

Views

Author

Keywords

Comments

Conjectures for o.g.f.s for this type of sequences appear in the PhD thesis by Simon Plouffe. See A001552 for the reference. These conjectures are proved in the link given in A196837. - Wolfdieter Lang, Oct 15 2011

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 813.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Column 10 of array A103438. Cf. A196837.

Programs

  • Mathematica
    Table[Total[Range[10]^n], {n, 0, 20}] (* T. D. Noe, Aug 09 2012 *)
  • Python
    def A001557(n): return sum(i**n for i in range(1,11)) # Chai Wah Wu, Oct 24 2024

Formula

a(n) = Sum_{j=1..10} j^n, n >= 0.
E.g.f.: exp(x) + exp(2*x) + exp(3*x) + exp(4*x) + exp(5*x) + exp(6*x) + exp(7*x) + exp(8*x) + exp(9*x) + exp(10*x). - Vladeta Jovovic, May 08 2002
From Wolfdieter Lang, Oct 15 2011: (Start)
O.g.f.: (2 - 11*x) *(5 - 220*x + 4070*x^2 - 41140*x^3 + 247049*x^4 - 896368*x^5 + 1903836*x^6 - 2143152*x^7 + 966240*x^8)/Product_{j=1..10} (1 - j*x).
From the e.g.f. via Laplace transformation. See the proof in a link under A196837.
(End)
a(n) = A001556(n) + A011557(n). - Michel Marcus, Jul 26 2013

Extensions

More terms from Jon E. Schoenfield, Mar 24 2010
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