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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A266557 Decimal expansion of the generalized Glaisher-Kinkelin constant A(10).

Original entry on oeis.org

1, 0, 1, 9, 1, 1, 0, 2, 3, 3, 3, 2, 9, 3, 8, 3, 8, 5, 3, 7, 2, 2, 1, 6, 4, 7, 0, 4, 9, 8, 6, 2, 9, 7, 5, 1, 3, 5, 1, 3, 4, 8, 1, 3, 7, 2, 8, 4, 0, 9, 9, 6, 0, 4, 4, 5, 9, 6, 4, 1, 4, 9, 4, 6, 7, 6, 5, 5, 4, 2, 8, 9, 5, 9, 3
Offset: 1

Views

Author

G. C. Greubel, Dec 31 2015

Keywords

Comments

Also known as the 10th Bendersky constant.

Examples

			1.01911023332938385372216470498629751351348137284099604...
		

Crossrefs

Cf. A019727 (A(0)), A074962 (A(1)), A243262 (A(2)), A243263 (A(3)), A243264 (A(4)), A243265 (A(5)), A266553 (A(6)), A266554 (A(7)), A266555 (A(8)), A266556 (A(9)), A266558 (A(11)), A266559 (A(12)), A260662 (A(13)), A266560 (A(14)), A266562 (A(15)), A266563 (A(16)), A266564 (A(17)), A266565 (A(18)), A266566 (A(19)), A266567 (A(20)).

Programs

  • Mathematica
    Exp[N[(BernoulliB[10]/4)*(Zeta[11]/Zeta[10]), 200]]

Formula

A(k) = exp(H(k)*B(k+1)/(k+1) - zeta'(-k)), where B(k) is the k-th Bernoulli number, H(k) the k-th harmonic number, and zeta'(x) is the derivative of the Riemann zeta function.
A(10) = exp(-zeta'(-10)) = exp((B(10)/4)*(zeta(11)/zeta(10))).
A(10) = exp(10! * Zeta(11) / (2^11 * Pi^10)). - Vaclav Kotesovec, Jan 01 2016

A013677 Decimal expansion of zeta(19).

Original entry on oeis.org

1, 0, 0, 0, 0, 0, 1, 9, 0, 8, 2, 1, 2, 7, 1, 6, 5, 5, 3, 9, 3, 8, 9, 2, 5, 6, 5, 6, 9, 5, 7, 7, 9, 5, 1, 0, 1, 3, 5, 3, 2, 5, 8, 5, 7, 1, 1, 4, 4, 8, 3, 8, 6, 3, 0, 2, 3, 5, 9, 3, 3, 0, 4, 6, 7, 6, 1, 8, 2, 3, 9, 4, 9, 7, 0, 5, 3, 4, 1, 3, 0, 9, 3, 1, 2, 6, 6, 4, 2, 2, 7, 1, 1, 8, 0, 7, 6, 3, 0
Offset: 1

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Author

Keywords

Examples

			1.0000019082127165539389256569577951013532585711448386302359330467618239...
		

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. 811.

Crossrefs

Programs

Formula

zeta(19) = Sum_{n >= 1} (A010052(n)/n^(19/2)) = Sum_{n >= 1} ( (floor(sqrt(n)) - floor(sqrt(n-1)))/n^(19/2) ). - Mikael Aaltonen, Feb 23 2015
zeta(19) = Product_{k>=1} 1/(1 - 1/prime(k)^19). - Vaclav Kotesovec, May 02 2020

A069095 Jordan function J_10(n).

Original entry on oeis.org

1, 1023, 59048, 1047552, 9765624, 60406104, 282475248, 1072693248, 3486725352, 9990233352, 25937424600, 61855850496, 137858491848, 288972178704, 576640565952, 1098437885952, 2015993900448, 3566920035096, 6131066257800
Offset: 1

Views

Author

Benoit Cloitre, Apr 05 2002

Keywords

Comments

a(n) is divisible by 264 = (2^3)*3*11 = A006863(5), except for n = 1, 2, 3 or 11. See Lugo. - Peter Bala, Jan 13 2024

References

  • L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 199, #3.

Crossrefs

Cf. A059379 and A059380 (triangle of values of J_k(n)), A000010 (J_1), A007434 (J-2), A059376 (J_3), A059377 (J_4), A059378 (J_5), A069091 - A069094 (J_6 through J_9).
Cf. A013669.

Programs

  • Maple
    f:= n -> n^10*mul(1-1/p^10, p=numtheory:-factorset(n)):
    map(f, [$1..30]); # Robert Israel, Jan 09 2015
  • Mathematica
    JordanJ[n_, k_] := DivisorSum[n, #^k*MoebiusMu[n/#] &]; f[n_] := JordanJ[n, 10]; Array[f, 21]
    f[p_, e_] := p^(10*e) - p^(10*(e-1)); a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Oct 12 2020 *)
  • PARI
    a(n) = sumdiv(n,d,d^10*moebius(n/d));

Formula

a(n) = Sum_{d|n} d^10*mu(n/d).
Multiplicative with a(p^e) = p^(10e)-p^(10(e-1)).
Dirichlet generating function: zeta(s-10)/zeta(s). - Ralf Stephan, Jul 04 2013
a(n) = n^10*Product_{distinct primes p dividing n} (1-1/p^10). - Tom Edgar, Jan 09 2015
Sum_{k=1..n} a(k) ~ n^11 / (11*zeta(11)). - Vaclav Kotesovec, Feb 07 2019
From Amiram Eldar, Oct 12 2020: (Start)
lim_{n->oo} (1/n) * Sum_{k=1..n} a(k)/k^10 = 1/zeta(11).
Sum_{n>=1} 1/a(n) = Product_{p prime} (1 + p^10/(p^10-1)^2) = 1.0009955309... (End)

A013958 a(n) = sigma_10(n), the sum of the 10th powers of the divisors of n.

Original entry on oeis.org

1, 1025, 59050, 1049601, 9765626, 60526250, 282475250, 1074791425, 3486843451, 10009766650, 25937424602, 61978939050, 137858491850, 289537131250, 576660215300, 1100586419201, 2015993900450, 3574014537275, 6131066257802, 10250010815226, 16680163512500, 26585860217050
Offset: 1

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Author

Keywords

Comments

If the canonical factorization of n into prime powers is the product of p^e(p) then sigma_k(n) = Product_p ((p^((e(p)+1)*k))-1)/(p^k-1).
Sum_{d|n} 1/d^k is equal to sigma_k(n)/n^k. So sequences A017665-A017712 also give the numerators and denominators of sigma_k(n)/n^k for k = 1..24. The power sums sigma_k(n) are in sequences A000203 (k=1), A001157-A001160 (k=2,3,4,5), A013954-A013972 for k = 6,7,...,24. - Ahmed Fares (ahmedfares(AT)my-deja.com), Apr 05 2001

Crossrefs

Programs

Formula

G.f.: Sum_{k>=1} k^10*x^k/(1-x^k). - Benoit Cloitre, Apr 21 2003
L.g.f.: -log(Product_{k>=1} (1 - x^k)^(k^9)) = Sum_{n>=1} a(n)*x^n/n. - Ilya Gutkovskiy, May 06 2017
From Amiram Eldar, Oct 29 2023: (Start)
Multiplicative with a(p^e) = (p^(10*e+10)-1)/(p^10-1).
Dirichlet g.f.: zeta(s)*zeta(s-10).
Sum_{k=1..n} a(k) = zeta(11) * n^11 / 11 + O(n^12). (End)

A079395 a(n) = prime(n)^11.

Original entry on oeis.org

2048, 177147, 48828125, 1977326743, 285311670611, 1792160394037, 34271896307633, 116490258898219, 952809757913927, 12200509765705829, 25408476896404831, 177917621779460413, 550329031716248441
Offset: 1

Views

Author

Jon Perry, Jan 06 2003

Keywords

Examples

			2^11 = 2048.
		

Crossrefs

Subsequence of A008455.
Cf. A013669.

Programs

Formula

From Amiram Eldar, Jan 24 2021: (Start)
Product_{n>=1} (1 + 1/a(n)) = zeta(11)/zeta(22).
Product_{n>=1} (1 - 1/a(n)) = 1/zeta(11) = 1/A013669. (End)

A351273 Sum of the 10th powers of the squarefree divisors of n.

Original entry on oeis.org

1, 1025, 59050, 1025, 9765626, 60526250, 282475250, 1025, 59050, 10009766650, 25937424602, 60526250, 137858491850, 289537131250, 576660215300, 1025, 2015993900450, 60526250, 6131066257802, 10009766650, 16680163512500, 26585860217050, 41426511213650, 60526250
Offset: 1

Views

Author

Wesley Ivan Hurt, Feb 05 2022

Keywords

Comments

Inverse Möbius transform of n^10 * mu(n)^2. - Wesley Ivan Hurt, Jun 08 2023

Examples

			a(4) = 1025; a(4) = Sum_{d|4} d^10 * mu(d)^2 = 1^10*1 + 2^10*1 + 4^10*0 = 1025.
		

Crossrefs

Cf. A008683 (mu), A013661, A013669.
Sum of the k-th powers of the squarefree divisors of n for k=0..10: A034444 (k=0), A048250 (k=1), A351265 (k=2), A351266 (k=3), A351267 (k=4), A351268 (k=5), A351269 (k=6), A351270 (k=7), A351271 (k=8), A351272 (k=9), this sequence (k=10).

Programs

  • Mathematica
    a[1] = 1; a[n_] := Times @@ (1 + FactorInteger[n][[;; , 1]]^10); Array[a, 100] (* Amiram Eldar, Feb 06 2022 *)
    Table[Total[Select[Divisors[n],SquareFreeQ]^10],{n,25}] (* Harvey P. Dale, Nov 20 2022 *)

Formula

a(n) = Sum_{d|n} d^10 * mu(d)^2.
Multiplicative with a(p^e) = 1 + p^10. - Amiram Eldar, Feb 06 2022
G.f.: Sum_{k>=1} mu(k)^2 * k^10 * x^k / (1 - x^k). - Ilya Gutkovskiy, Feb 06 2022
Sum_{k=1..n} a(k) ~ c * n^11, where c = zeta(11)/(11*zeta(2)) = 0.0552934... . - Amiram Eldar, Nov 10 2022

A351607 a(n) = n^9 * Sum_{d^2|n} 1 / d^9.

Original entry on oeis.org

1, 512, 19683, 262656, 1953125, 10077696, 40353607, 134479872, 387440172, 1000000000, 2357947691, 5169858048, 10604499373, 20661046784, 38443359375, 68853956608, 118587876497, 198369368064, 322687697779, 513000000000, 794280046581, 1207269217792, 1801152661463
Offset: 1

Views

Author

Wesley Ivan Hurt, Feb 14 2022

Keywords

Crossrefs

Sequences of the form n^k * Sum_{d^2|n} 1/d^k for k = 0..10: A046951 (k=0), A340774 (k=1), A351600 (k=2), A351601 (k=3), A351602 (k=4), A351603 (k=5), A351604 (k=6), A351605 (k=7), A351606 (k=8), this sequence (k=9), A351608 (k=10).
Cf. A013669.

Programs

  • Mathematica
    f[p_, e_] := p^9*(p^(9*e) - p^(9*Floor[(e - 1)/2]))/(p^9 - 1); a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 30] (* Amiram Eldar, Nov 13 2022 *)
  • PARI
    a(n) = n^9*sumdiv(n, d, if (issquare(d), 1/sqrtint(d^9))); \\ Michel Marcus, Feb 15 2022

Formula

Multiplicative with a(p^e) = p^9*(p^(9*e) - p^(9*floor((e-1)/2)))/(p^9 - 1). - Sebastian Karlsson, Mar 03 2022
Sum_{k=1..n} a(k) ~ c * n^10, where c = zeta(11)/10 = 0.100049... . - Amiram Eldar, Nov 13 2022

A352038 Sum of the 10th powers of the odd proper divisors of n.

Original entry on oeis.org

0, 1, 1, 1, 1, 59050, 1, 1, 59050, 9765626, 1, 59050, 1, 282475250, 9824675, 1, 1, 3486843451, 1, 9765626, 282534299, 25937424602, 1, 59050, 9765626, 137858491850, 3486843451, 282475250, 1, 576660215300, 1, 1, 25937483651, 2015993900450, 292240875, 3486843451
Offset: 1

Views

Author

Wesley Ivan Hurt, Mar 01 2022

Keywords

Examples

			a(10) = 9765626; a(10) = Sum_{d|10, d<10, d odd} d^10 = 1^10 + 5^10 = 9765626.
		

Crossrefs

Sum of the k-th powers of the odd proper divisors of n for k=0..10: A091954 (k=0), A091570 (k=1), A351647 (k=2), A352031 (k=3), A352032 (k=4), A352033 (k=5), A352034 (k=6), A352035 (k=7), A352036 (k=8), A352037 (k=9), this sequence (k=10).

Programs

  • Mathematica
    f[2, e_] := 1; f[p_, e_] := (p^(10*e+10) - 1)/(p^10 - 1); a[1] = 0; a[n_] := Times @@ f @@@ FactorInteger[n] - If[OddQ[n], n^10, 0]; Array[a, 60] (* Amiram Eldar, Oct 11 2023 *)
  • Python
    from math import prod
    from sympy import factorint
    def A352038(n): return prod((p**(10*(e+1))-1)//(p**10-1) for p, e in factorint(n).items() if p > 2) - (n**10 if n % 2 else 0) # Chai Wah Wu, Mar 01 2022

Formula

a(n) = Sum_{d|n, d
G.f.: Sum_{k>=1} (2*k-1)^10 * x^(4*k-2) / (1 - x^(2*k-1)). - Ilya Gutkovskiy, Mar 02 2022
From Amiram Eldar, Oct 11 2023: (Start)
a(n) = A321814(n) - n^10*A000035(n).
Sum_{k=1..n} a(k) ~ c * n^11, where c = (zeta(11)-1)/22 = 0.0000224631... . (End)

A352056 Sum of the 10th powers of the divisor complements of the odd proper divisors of n.

Original entry on oeis.org

0, 1024, 59049, 1048576, 9765625, 60467200, 282475249, 1073741824, 3486843450, 10000001024, 25937424601, 61918412800, 137858491849, 289254656000, 576660215299, 1099511627776, 2015993900449, 3570527693824, 6131066257801, 10240001048576, 16680163512499
Offset: 1

Author

Wesley Ivan Hurt, Mar 01 2022

Keywords

Examples

			a(10) = 10^10 * Sum_{d|10, d<10, d odd} 1 / d^10 = 10^10 * (1/1^10 + 1/5^10) = 10000001024.
		

Crossrefs

Sum of the k-th powers of the divisor complements of the odd proper divisors of n for k=0..10: A091954 (k=0), A352047 (k=1), A352048 (k=2), A352049 (k=3), A352050 (k=4), A352051 (k=5), A352052 (k=6), A352053 (k=7), A352054 (k=8), A352055 (k=9), this sequence (k=10).

Programs

  • Mathematica
    A352056[n_]:=DivisorSum[n,1/#^10&,#A352056,50] (* Paolo Xausa, Aug 10 2023 *)
    a[n_] := DivisorSigma[-10, n/2^IntegerExponent[n, 2]] * n^10 - Mod[n, 2]; Array[a, 100] (* Amiram Eldar, Oct 13 2023 *)
  • PARI
    a(n) = n^10 * sigma(n >> valuation(n, 2), -10) - n % 2; \\ Amiram Eldar, Oct 13 2023

Formula

a(n) = n^10 * Sum_{d|n, d
G.f.: Sum_{k>=2} k^10 * x^k / (1 - x^(2*k)). - Ilya Gutkovskiy, May 19 2023
From Amiram Eldar, Oct 13 2023: (Start)
a(n) = A321814(n) * A006519(n)^10 - A000035(n).
Sum_{k=1..n} a(k) = c * n^11 / 11, where c = 2047*zeta(11)/2048 = 1.00000566605... . (End)

A293904 Decimal expansion of zeta(21).

Original entry on oeis.org

1, 0, 0, 0, 0, 0, 0, 4, 7, 6, 9, 3, 2, 9, 8, 6, 7, 8, 7, 8, 0, 6, 4, 6, 3, 1, 1, 6, 7, 1, 9, 6, 0, 4, 3, 7, 3, 0, 4, 5, 9, 6, 6, 4, 4, 6, 6, 9, 4, 7, 8, 4, 9, 3, 7, 6, 0, 0, 2, 0, 7, 4, 8, 7, 3, 7, 6, 5, 9, 6, 8, 3, 9, 0, 8, 7, 8, 9, 8, 1, 5, 9, 8, 3, 3, 8, 7, 6, 6
Offset: 1

Author

Frank Ellermann, Oct 19 2017

Keywords

Comments

Web searches find 1.0000004769329867878 in Python tools. Simon Plouffe published 1000 digits for zeta(9) up to zeta(2051) many years ago.

Examples

			1.000000476932986787806...
		

Programs

  • Mathematica
    RealDigits[Zeta[21], 10, 100][[1]] (* Amiram Eldar, May 31 2021 *)
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