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 1-7 of 7 results.

A003854 Order of simple Chevalley group D_8(q), q = prime power.

Original entry on oeis.org

911666827031785075278550369566720000, 393736985584514548835738283681336315795223487793070080000, 1649493899207759406688161287839326786813727965837588934265143296000000000
Offset: 1

Views

Author

N. J. A. Sloane

Keywords

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. xvi.
  • H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.

Links

Crossrefs

Cf. A000961, A003808, A003837, A003848, A003850, A003851, A003852, A003853.

Programs

  • Mathematica
    d[q_, n_] := q^(n*(n-1)) * (q^n-1) * Product[q^(2*k) - 1, {k, 1, n-1}] / GCD[4, q^n-1]; Table[d[q, 8], {q, Select[Range[10], PrimePowerQ]}] (* Amiram Eldar, Jun 24 2025 *)

Formula

a(n) = d(A000961(n+1),8) where d(q,n) is defined in A003837. - Sean A. Irvine, Sep 17 2015

Extensions

More terms from Sean A. Irvine, Sep 17 2015

A003848 Order of (usually) simple Chevalley group D_2(q), q = prime power.

Original entry on oeis.org

36, 144, 3600, 3600, 28224, 254016, 129600, 435600, 1192464, 16646400, 5992704, 11696400, 36869184, 60840000, 96589584, 148352400, 221414400, 1071645696, 640494864, 1186113600, 1578631824, 2692364544, 3457440000, 5537145744, 10539075600, 12873171600, 68685926400
Offset: 1

Views

Author

N. J. A. Sloane

Keywords

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. xvi.
  • H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.

Links

Crossrefs

Cf. A000961, A003808, A003837, A003850, A003851, A003852, A003853, A003854.

Programs

  • Mathematica
    d[q_, n_] := q^(n*(n-1)) * (q^n-1) * Product[q^(2*k) - 1, {k, 1, n-1}] / GCD[4, q^n-1]; Table[d[q, 2], {q, Select[Range[50], PrimePowerQ]}] (* Amiram Eldar, Jun 24 2025 *)

Formula

a(n) = d(A000961(n+1),2) where d(q,n) is defined in A003837. - Sean A. Irvine, Sep 17 2015

A003850 Order of simple Chevalley group D_4(q), q = prime power.

Original entry on oeis.org

174182400, 4952179814400, 67010895544320000, 8911539000000000000, 112554991177798901760000, 19031213036231093492121600, 129182006871144805294080000, 35749625435272978955066880000
Offset: 1

Views

Author

N. J. A. Sloane

Keywords

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. xvi.
  • H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.

Links

Crossrefs

Cf. A000961, A003808, A003837, A003848, A003851, A003852, A003853, A003854.

Programs

  • Mathematica
    d[q_, n_] := q^(n*(n-1)) * (q^n-1) * Product[q^(2*k) - 1, {k, 1, n-1}] / GCD[4, q^n-1]; Table[d[q, 4], {q, Select[Range[20], PrimePowerQ]}] (* Amiram Eldar, Jun 24 2025 *)

Formula

a(n) = d(A000961(n+1),4) where d(q,n) is defined in A003837. - Sean A. Irvine, Sep 17 2015

A003851 Order of simple Chevalley group D_5(q), q = prime power.

Original entry on oeis.org

23499295948800, 1289512799941305139200, 1154606796534757164318720000, 6807663884896875000000000000000, 52386144472825139642572263782154240000, 42863636354909175368011800612065142374400, 2154683673871373733440812330742751559680000
Offset: 1

Views

Author

N. J. A. Sloane

Keywords

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. xvi.
  • H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.

Links

Crossrefs

Cf. A000961, A003808, A003837, A003848, A003850, A003852, A003853, A003854.

Programs

  • Mathematica
    d[q_, n_] := q^(n*(n-1)) * (q^n-1) * Product[q^(2*k) - 1, {k, 1, n-1}] / GCD[4, q^n-1]; Table[d[q, 5], {q, Select[Range[20], PrimePowerQ]}] (* Amiram Eldar, Jun 24 2025 *)

Formula

a(n) = d(A000961(n+1),5) where d(q,n) is defined in A003837. - Sean A. Irvine, Sep 17 2015

Extensions

More terms from Sean A. Irvine, Sep 17 2015

A003852 Order of simple Chevalley group D_6(q), q = prime power.

Original entry on oeis.org

50027557148216524800, 6762844700608770238252960972800, 5081732431326820541485324550799360000000, 3246978048053003424316406250000000000000000000, 14630778277213500974314928221817819519899234908241920000
Offset: 1

Views

Author

N. J. A. Sloane

Keywords

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. xvi.
  • H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.

Links

Crossrefs

Cf. A000961, A003808, A003837, A003848, A003850, A003851, A003853, A003854.

Programs

  • Mathematica
    d[q_, n_] := q^(n*(n-1)) * (q^n-1) * Product[q^(2*k) - 1, {k, 1, n-1}] / GCD[4, q^n-1]; Table[d[q, 6], {q, Select[Range[20], PrimePowerQ]}] (* Amiram Eldar, Jun 24 2025 *)

Formula

a(n) = d(A000961(n+1),6) where d(q,n) is defined in A003837. - Sean A. Irvine, Sep 17 2015

Extensions

a(5) from Sean A. Irvine, Sep 17 2015

A003853 Order of simple Chevalley group D_7(q), q = prime power.

Original entry on oeis.org

1691555775522928280469504000, 11470635634813395742481912276441576767488000, 5722569627753465177061732369386833143098255605760000000, 967724409898859060146424426078796386718750000000000000000000000, 39242041156758982253792290541798244252619818128923898602839750047956992000000
Offset: 1

Views

Author

N. J. A. Sloane

Keywords

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. xvi.
  • H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.

Links

Crossrefs

Cf. A003846. - R. J. Mathar, Oct 28 2008
Cf. A000961, A003808, A003837, A003848, A003850, A003851, A003852, A003854.

Programs

  • Mathematica
    d[q_, n_] := q^(n*(n-1)) * (q^n-1) * Product[q^(2*k) - 1, {k, 1, n-1}] / GCD[4, q^n-1]; Table[d[q, 7], {q, Select[Range[10], PrimePowerQ]}] (* Amiram Eldar, Jun 24 2025 *)

Formula

a(n) = d(A000961(n+1),7) where d(q,n) is defined in A003837. - Sean A. Irvine, Sep 17 2015

Extensions

More terms from Sean A. Irvine, Sep 17 2015

A155025 Primes p=A000040(n) with nonprime index n such that the concatenation n//p is a composite number.

Original entry on oeis.org

2, 19, 23, 29, 43, 47, 53, 71, 73, 79, 89, 97, 101, 107, 131, 137, 139, 163, 167, 173, 193, 223, 227, 229, 233, 239, 257, 281, 293, 307, 311, 313, 317, 337, 347, 349, 359, 373, 379, 383, 389, 397, 409, 419, 433, 443, 449, 457, 463, 467, 491, 499, 503, 521, 541, 557, 569
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Jan 19 2009

Keywords

Examples

			For the nonprime n=1, p = prime(n) = 2, the concatenation is 12 is composite, and p is added to the sequence.
For the nonprime n=8, p = prime(8) = 19, the concatenation 819 is composite, and p=19 is added to the sequence.
For the nonprime n=12, p = prime(12) = 37, the concatenation 1237 is prime, so p=37 is not added to the sequence.

Links

Crossrefs

Cf. A000040, A003808, A141468, A155030.

Programs

  • Mathematica
    cnQ[{n_,p_}]:=!PrimeQ[n]&&!PrimeQ[FromDigits[Flatten[ IntegerDigits/@ {n,p}]]]; Transpose[Select[Table[{n,Prime[n]},{n,150}],cnQ]][[2]] (* Harvey P. Dale, Dec 18 2012 *)

Extensions

Definition clarified, sequence extended by R. J. Mathar, Oct 14 2009
Showing 1-7 of 7 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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