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 1-9 of 9 results.

A108764 Products of exactly two supersingular primes (A002267).

Original entry on oeis.org

4, 6, 9, 10, 14, 15, 21, 22, 25, 26, 33, 34, 35, 38, 39, 46, 49, 51, 55, 57, 58, 62, 65, 69, 77, 82, 85, 87, 91, 93, 94, 95, 115, 118, 119, 121, 123, 133, 141, 142, 143, 145, 155, 161, 169, 177, 187, 203, 205, 209, 213, 217, 221, 235, 247, 253, 287, 289, 295, 299
Offset: 1

Views

Author

Jonathan Vos Post, Jun 17 2005

Keywords

Comments

There are exactly 15 supersingular primes: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 47, 59 and 71 (A002267). The supersingular primes are exactly the set of primes that divide the group order of the Monster group.
Peter Luschny's link shows how this sequence may be connected to Schinzel-Sierpinski conjecture and the Calkin-Wilf tree.

Examples

			1207 = 17 * 71, 3337 = 47 * 71.
		

References

  • E. Dijkstra, Selected Writings on Computing, Springer, 1982, p. 232.
  • Ogg, A. P. "Modular Functions." In The Santa Cruz Conference on Finite Groups. Held at the University of California, Santa Cruz, Calif., 1979 (Ed. B. Cooperstein and G. Mason). Providence, RI: Amer. Math. Soc., pp. 521-532, 1980.
  • Silverman, J. H. The Arithmetic of Elliptic Curves II. New York: Springer-Verlag, 1994.

Crossrefs

Programs

  • Mathematica
    Union[ Times @@@ Tuples[{2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 47, 59, 71}, 2]] (*Robert G. Wilson v, Feb 11 2011 *)

Formula

{a(n)} = {p*q: p in A002267 and q in A002267}.

A212554 Products of supersingular primes (A002267).

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 59, 60, 62, 63, 64, 65, 66, 68, 69, 70, 71, 72, 75, 76, 77, 78, 80, 81, 82, 84, 85, 87, 88, 90, 91, 92, 93, 94, 95, 96, 98, 99, 100
Offset: 1

Views

Author

Ben Branman, May 21 2012

Keywords

Comments

The initial 1 is included because it has no non-supersingular prime factors.
Many of the early terms divide the order of the monster simple group (see A174670). The first n such that a(n) does not belong to A174670 is a(204)=289.

References

  • J. H. Conway, R. T. Curtis, S. P. Norton, R. A. Parker and R. A. Wilson, ATLAS of Finite Groups. Oxford Univ. Press, 1985 [for best online version see https://oeis.org/wiki/Welcome#Links_to_Other_Sites].
  • J. H. Conway and S. P. Norton, Monstrous Moonshine, Bull. Lond. Math. Soc. 11 (1979) 308-339.
  • A. P. Ogg, Modular functions, in The Santa Cruz Conference on Finite Groups (Univ. California, Santa Cruz, Calif., 1979), pp. 521-532, Proc. Sympos. Pure Math., 37, Amer. Math. Soc., Providence, R.I., 1980.

Crossrefs

Cf. A002267, A174670, A108764 (products of exactly two supersingular primes).

Programs

  • Mathematica
    ps = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 47, 59, 71}; fQ[n_] := Module[{p = Transpose[FactorInteger[n]][[1]]}, Complement[p, ps] == {}]; Join[{1}, Select[Range[2,1000], fQ]] (* T. D. Noe, May 21 2012 *)

Formula

log a(n) ~ k*n^(1/15). - Charles R Greathouse IV, Jul 18 2012

A212582 Products of exactly three supersingular primes (A002267).

Original entry on oeis.org

8, 12, 18, 20, 27, 28, 30, 42, 44, 45, 50, 52, 63, 66, 68, 70, 75, 76, 78, 92, 98, 99, 102, 105, 110, 114, 116, 117, 124, 125, 130, 138, 147, 153, 154, 164, 165, 170, 171, 174, 175, 182, 186, 188, 190, 195, 207, 230, 231, 236, 238, 242, 245, 246, 255, 261
Offset: 1

Views

Author

Jonathan Vos Post, May 21 2012

Keywords

Comments

The smallest "triprime" or "3-almost prime" not in this sequence is 148 = 2 * 2 * 37, as 37 is smallest prime which is not a supersingular prime.

Crossrefs

Cf. A002267, A014612, A108764 (products of exactly two supersingular primes), A212554 (products of supersingular primes).

Programs

  • Mathematica
    Union[Times @@@ Tuples[{2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 47, 59, 71}, 3]] (* T. D. Noe, May 21 2012 *)

Formula

i * j * k such that i, j, k are each in A002267, not necessarily distinct.

A001379 Degrees of irreducible representations of Monster group M.

Original entry on oeis.org

1, 196883, 21296876, 842609326, 18538750076, 19360062527, 293553734298, 3879214937598, 36173193327999, 125510727015275, 190292345709543, 222879856734249, 1044868466775133, 1109944460516150, 2374124840062976, 8980616927734375, 8980616927734375, 15178147608537368
Offset: 1

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Author

Keywords

Comments

The sequence contains 194 terms, of which 170 are distinct. The only triple of repeated terms is a(123) = a(124) = a(125) = 5514132424881463208443904. The rest of the repeated terms are pairs, for example a(16) = a(17) = 8980616927734375. - Omar E. Pol, Nov 28 2014

References

  • J. H. Conway, R. T. Curtis, S. P. Norton, R. A. Parker and R. A. Wilson, ATLAS of Finite Groups. Oxford Univ. Press, 1985 [for best online version see https://oeis.org/wiki/Welcome#Links_to_Other_Sites].

Crossrefs

Programs

  • GAP
    List(Irr(CharacterTable("M")), chi->chi[1]); # Eric M. Schmidt, Jul 15 2012

A174670 Divisors of the order of the Monster group.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 59, 60, 62, 63, 64, 65, 66, 68, 69, 70, 71, 72, 75, 76, 77, 78, 80
Offset: 1

Views

Author

Reinhard Zumkeller, Apr 02 2010

Keywords

Comments

Let Mnr = A001228(26) = 808017424794512875886459904961710757005754368000000000, also called the Monster number, cf. A003131;
the sequence is finite with A174601(26) = 424488960 terms;
a(n) = n for n < 37 = A053669(Mnr) = (smallest prime not in A002267);
24 of the 26 terms of A001228 are divisors of Mnr, the exceptions are A001228(19) and A001228(23), orders of groups Ly and J4;
also the first 36 factorials and the first 11 primorials are divisors of Mnr (cf. examples);
A174671 gives divisors of Mnr sorted into decreasing order: A174671(n)=a(424488960-n+1)=Mnr/a(n).

Examples

			......... a(30) = A002110(3) = ........... 30 = 5#;
........ a(101) = A000142(5) = .......... 120 = 5!;
........ a(159) = A002110(4) = .......... 210 = 7#;
........ a(398) = A000142(6) = .......... 720 = 6!;
........ a(888) = A002110(5) = ......... 2310 = 11#;
....... a(1461) = A000142(7) = ......... 5040 = 7!;
....... a(1931) = A001228(1) = ......... 7920;
....... a(4207) = A002110(6) = ........ 30030 = 13#;
....... a(4952) = A000142(8) = ........ 40320 = 8!;
....... a(7859) = A001228(2) = ........ 95040;
...... a(10787) = A001228(3) = ....... 175560;
...... a(15477) = A000142(9) = ....... 362880 = 9!;
...... a(17056) = A001228(4) = ....... 443520;
...... a(18257) = A002110(7) = ....... 510510 = 17#;
...... a(19792) = A001228(5) = ....... 604800;
...... a(44571) = A000142(10) = ..... 3628800 = 10!;
...... a(67510) = A002110(8) = ...... 9699690 = 19#;
...... a(68918) = A001228(6) = ..... 10200960;
..... a(118553) = A000142(11) = .... 39916800 = 11!;
..... a(123436) = A001228(7) = ..... 44352000;
..... a(129447) = A001228(8) = ..... 50232960;
..... a(223787) = A002110(9) = .... 223092870 = 23#;
..... a(231256) = A001228(9) = .... 244823040;
..... a(291999) = A000142(12) = ... 479001600 = 12!.
..... a(360936) = A001228(10) = ... 898128000;
..... a(584543) = A001228(11) = .. 4030387200;
.. a(424488960) = A001228(26) = ......... Mnr, the last term.
		

Programs

  • PARI
    divisors(808017424794512875886459904961710757005754368000000000)
    \\ Warning: output is ~13 GB.
    \\ Charles R Greathouse IV, Sep 02 2015

A003131 Order of Monster simple group.

Original entry on oeis.org

8, 0, 8, 0, 1, 7, 4, 2, 4, 7, 9, 4, 5, 1, 2, 8, 7, 5, 8, 8, 6, 4, 5, 9, 9, 0, 4, 9, 6, 1, 7, 1, 0, 7, 5, 7, 0, 0, 5, 7, 5, 4, 3, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 54

Views

Author

Keywords

Examples

			808017424794512875886459904961710757005754368000000000.
		

References

  • J. H. Conway, R. T. Curtis, S. P. Norton, R. A. Parker and R. A. Wilson, ATLAS of Finite Groups. Oxford Univ. Press, 1985 [for best online version see https://oeis.org/wiki/Welcome#Links_to_Other_Sites], p. 228.
  • J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 296.
  • J. H. Conway and R. K. Guy, The Book of Numbers, Copernicus Press, New York, 1996, p. 62.
  • C. A. Pickover, The Math Book, Sterling, NY, 2009; see p. 474.

Crossrefs

Programs

  • PARI
    2^46 * 3^20 * 5^9 * 7^6 * 11^2 * 13^3 * 17 * 19 * 23 * 29 * 31 * 41 * 47 * 59 * 71 \\ Charles R Greathouse IV, Oct 31 2014

Formula

Equals A001228(26) = Product_{n=1..15} A002267(n)^A051161(A049084(A002267(n))) = Sum_{n=0..53} a(53-n)*10^n = h(53) with h(n) = 10*h(n-1) + a(n) for n > 0, h(0) = a(0). - Reinhard Zumkeller, Apr 02 2010

A051161 a(n) is the exponent of n-th prime in the order (A003131) of the Monster simple group.

Original entry on oeis.org

46, 20, 9, 6, 2, 3, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 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, 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, 0, 0, 0, 0, 0, 0
Offset: 1

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Author

Keywords

Comments

a(n)=0 for n > 20.
Product_{k>0} (a(k) + 1) = A174601(26). - Reinhard Zumkeller, Apr 02 2010

Crossrefs

A174848 Squarefree kernels of orders of sporadic simple groups.

Original entry on oeis.org

330, 330, 43890, 2310, 210, 53130, 2310, 9690, 53130, 2310, 3570, 79170, 30030, 1360590, 53130, 53130, 30030, 43890, 177521190, 1607970, 11741730, 690690, 75992317170, 340510170, 325046311590, 1618964990108856390
Offset: 1

Views

Author

Reinhard Zumkeller, Apr 02 2010

Keywords

Comments

a(n) = A007947(A001228(n)).

Examples

			a(1) = 2*3*5*11;
a(2) = 2*3*5*11;
a(3) = 2*3*5*7*11*19;
a(4) = 2*3*5*7*11 = 11#;
a(5) = 2*3*5*7 = 7#;
a(6) = 2*3*5*7*11*23;
a(7) = 2*3*5*7*11 = 11#;
a(8) = 2*3*5*17*19;
a(9) = 2*3*5*7*11*23;
a(10) = 2*3*5*7*11 = 11#;
a(11) = 2*3*5*7*17;
a(12) = 2*3*5*7*13*29;
a(13) = 2*3*5*7*11*13 = 13#;
a(14) = 2*3*5*7*11*19*31;
a(15) = 2*3*5*7*11*23;
a(16) = 2*3*5*7*11*23;
a(17) = 2*3*5*7*11*13 = 13#;
a(18) = 2*3*5*7*11*19;
a(19) = 2*3*5*7*11*31*37*67;
a(20) = 2*3*5*7*13*19*31;
a(21) = 2*3*5*7*11*13*17*23;
a(22) = 2*3*5*7*11*13*23;
a(23) = 2*3*5*7*11*23*29*31*37*43;
a(24) = 2*3*5*7*11*13*17*23*29;
a(25) = 2*3*5*7*11*13*17*19*23*31*47;
a(26) = PROD(A002267(k): 1<=k<=15) = 2*3*5*7*11*13*17*19*23*29*31*41*47*59*71.
		

Crossrefs

Cf. A174670.

A173105 The 15 supersingular primes written in octal.

Original entry on oeis.org

2, 3, 5, 7, 13, 15, 21, 23, 27, 35, 37, 51, 57, 73, 107
Offset: 1

Views

Author

Jonathan Vos Post, Feb 09 2010

Keywords

Comments

The supersingular primes are the primes that divide the order of the Monster group.

Crossrefs

Formula

a(n) = A007094(A002267(n)).
Showing 1-9 of 9 results.