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 10 results.

A165710 Partial sums of A046882.

Original entry on oeis.org

1, 2, 6, 46662, 1333735776850284124449081472890438
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Mathematica
    Accumulate[Table[(n!)^n!,{n,0,5}]]  (* Harvey P. Dale, Apr 01 2011 *)

Formula

a(n) = Sum_{k=0..n} (k!)^(k!) = 1 + A165711(n).

Extensions

Definition simplified by R. J. Mathar, Sep 25 2009

A062961 Number of divisors of n!^n! (A046882).

Original entry on oeis.org

1, 1, 3, 49, 1825, 5285401, 2993246641, 5164747323361921, 37003141448637678721, 485526598340984090835841, 11097683374342583428355232001, 6485725972943960604540744581217509068801
Offset: 0

Views

Author

Jason Earls, Jul 22 2001

Keywords

Programs

  • PARI
    for(n=0,22,print(numdiv(n!^n!)))

Extensions

More terms from Vladeta Jovovic, Jul 26 2001

A165812 Ultraprimorials: a(n) = p#^p#.

Original entry on oeis.org

1, 4, 46656, 205891132094649000000000000000000000000000000
Offset: 0

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Author

Keywords

Comments

The n-th Primorial raised to its own power.
Terms from a(4) on have 488, 7770, 134461 and 2913994 digits (A195188) and are too large to be listed explicitly.

Crossrefs

Programs

  • Maple
    P:=proc(i) local a,n; a:=1; print(1); for n from 1 by 1 to i do a:=a*ithprime(n); print(a^a); od; end: P(10);

Formula

a(n) = A000312(A002110(n)) . [R. J. Mathar, Sep 29 2009]

Extensions

Slightly edited by R. J. Mathar, Sep 29 2009

A100685 Powers of factorials A000142.

Original entry on oeis.org

1, 2, 4, 6, 8, 16, 24, 32, 36, 64, 120, 128, 216, 256, 512, 576, 720, 1024, 1296, 2048, 4096, 5040, 7776, 8192, 13824, 14400, 16384, 32768, 40320, 46656, 65536, 131072, 262144, 279936, 331776, 362880, 518400, 524288, 1048576, 1679616, 1728000
Offset: 1

Views

Author

Kyle Schalm and Jonathan Sondow, Dec 08 2004

Keywords

Comments

Subsequence of A001013. Supersequence of A036740 without its first term.
Supersequence also of A046882 and A055209 without their first terms. - Jonathan Sondow and Robert G. Wilson v, Dec 19 2004

Examples

			24 = (4!)^1 and 36 = (3!)^2.
		

Crossrefs

Cf. also A046882 and A055209.
Subsequences: A000079, A000400, A009968.

Programs

  • Mathematica
    With[{ln = Log[10!]}, Table[With[{f = m!}, Table[f^j, {j, 0, Floor[ln/Log[f]]}]], {m, 2, 10}]] //Flatten //Union

Formula

Sum_{n>=1} 1/a(n) = 1 + A331373. - Amiram Eldar, Nov 21 2021

A195529 Ultracompositorial: Compositorials raised to the power of themselves.

Original entry on oeis.org

1, 256, 1333735776850284124449081472843776
Offset: 0

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Author

Kausthub Gudipati, Sep 21 2011

Keywords

Comments

Next term (192^192) has 439 digits.

Crossrefs

Programs

Formula

a(n) = A000312(A036691(n)). - Amiram Eldar, Jul 20 2025
a(2) = A114993(2). - R. J. Mathar, Aug 22 2025

Extensions

a(2) corrected by Franklin T. Adams-Watters, Sep 21 2011

A260614 Product of the first n ultrafactorials ((n!)^(n!)).

Original entry on oeis.org

1, 1, 4, 186624, 248907105618907424441185380787996852224
Offset: 0

Views

Author

Matthew Campbell, Aug 13 2015

Keywords

Comments

a(6) is about 10^2345.
This could be called a superultrafactorial by analogy with factorial and superfactorial.

Examples

			a(3) = (1!)^(1!) * (2!)^(2!) * (3!)^(3!) = 1^1 * 2^2 * 6^6 = 1 * 4 * 46656 = 186624.
		

Crossrefs

Programs

  • Magma
    [Factorial(n)^Factorial(n): n in [0..5]]; // Vincenzo Librandi, Aug 29 2015
  • Mathematica
    Table[Product[(m!)^(m!), {m, 0, n}], {n, 0, 5}]
  • PARI
    a(n)=prod(k=2,n,k!^k!) \\ Charles R Greathouse IV, Aug 14 2015
    

Formula

a(n) = Product_{k=1..n} A046882(k).

A275587 a(1) = 0; thereafter a(n) = s^s where s = Sum_{k=1..n-1} a(k).

Original entry on oeis.org

0, 1, 1, 4, 46656
Offset: 1

Views

Author

Rick L. Shepherd, Aug 02 2016

Keywords

Comments

a(2) = 1 by the convention that 0^0 = 1. a(6) = 46662^46662 = 1471657830...9021753344, which has 217864 decimal digits.

Crossrefs

Programs

  • Mathematica
    a[0] = 0; a[1] = 1; a[n_] := a[n] = #^# &@ Sum[a[k], {k, 1, n - 1}]; Table[a[n], {n, 0, 5}] (* Michael De Vlieger, Aug 04 2016 *)
  • PARI
    a(n) = local(s); if(n==1, 0, if(n>1, s = sum(k=1, n - 1, a(k)); s^s))

A073279 Number of digits of n!^n! (ultrafactorial numbers).

Original entry on oeis.org

1, 1, 1, 5, 34, 250, 2058, 18661, 185695, 2017527, 23804069, 303413813, 4157895295, 60989187252, 953766105164, 15844435971349, 278704524938621, 5175632136205088, 101198102131888304, 2078318050691940125, 44731639502987747576, 1006917859088311808499
Offset: 0

Views

Author

Rick L. Shepherd, Jul 23 2002

Keywords

Crossrefs

Cf. A046882 (ultrafactorial numbers), A000142 (n!), A034886 (digits of n!).

Programs

  • Mathematica
    Table[1 + Floor[n!*Log10[n!]], {n, 0, 21}] (* Arkadiusz Wesolowski, Oct 13 2012 *)
  • PARI
    for(n=0,8,print1(length(Str(n!^n!)),","))

Formula

a(n) = floor(log(n!^n!)/log(10)) + 1.

Extensions

More terms from Arkadiusz Wesolowski, Jul 04 2012
Terms a(17) to a(21) corrected by Arkadiusz Wesolowski, Oct 13 2012

A110094 Startorial primes.

Original entry on oeis.org

2, 3, 5, 7, 23, 719, 5039, 1451521, 2903041, 5806081, 46448639, 92897281, 371589121, 10032906239, 30098718719, 270888468479, 812665405439, 7313988648961, 21941965946881, 89874292518420479
Offset: 1

Views

Author

Jonathan Vos Post, Sep 04 2005

Keywords

Comments

These are primes of the form A109834 startorials (base 10) +1 or -1. This is by analogy to factorial primes (A002981), superfactorial primes (A073828), hyperfactorial primes, ultrafactorial primes (comment in A046882), subfactorial primes (A100015), double factorial primes (A080778), multifactorial primes (A037083).

Crossrefs

Formula

{a(n)} = {A109834(k)+1 an element of A000040, or A109834(k)-1 an element of A000040, for some k}.

A174212 Ultradoublefactorials: a(n) = (n!!)^(n!!).

Original entry on oeis.org

1, 1, 4, 27, 16777216, 437893890380859375, 500702078263459319174537025249570888246709955377400223021257741084821677152403456
Offset: 0

Views

Author

Keywords

Comments

The next term (a(8)) has 993 digits. - Harvey P. Dale, Aug 17 2017

Examples

			For n=4 the doublefactorial is n!! = 4*2 = 8 and a(n) = n!!^n!! = 8^8 = 16777216.
		

Crossrefs

Programs

  • Maple
    P:=proc(i) local a,n; for n from 0 by 1 to i do print(doublefactorial(n)^doublefactorial(n)); od; end: P(10);
  • Mathematica
    udf[n_]:=Module[{c=n!!},c^c]; Array[udf,7,0] (* Harvey P. Dale, Aug 17 2017 *)

Formula

a(n) = A006882(n)^A006882(n).
Sum_{n>=1} 1/a(n) = A134877. - Amiram Eldar, Nov 11 2020
Showing 1-10 of 10 results.