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 1-3 of 3 results.

A038785 Number of nonisomorphic circulant self-complementary directed p^2-graphs, indexed by odd primes p.

Original entry on oeis.org

3, 214, 399472, 10481104587335128, 123992391755402970674764, 81988033818127290961563099285346969398730, 4480981113642949878240780781141254929604041319893664
Offset: 1

Views

Author

N. J. A. Sloane, May 04 2000

Keywords

Comments

a(p^2)=A038789(p^2) for p=4k-1

Links

Crossrefs

Cf. A049309.

Extensions

More terms from Valery A. Liskovets, May 09 2001

A038788 Non-Cayley-isomorphic circulant self-complementary directed p^2-graphs, indexed by odd primes p.

Original entry on oeis.org

1, 4, 4, 16, 64, 400, 900, 8836, 355216, 1201216, 53523856, 690217984, 2494003600, 33255899044, 1666350520384, 85680866908816, 320296595636224, 16939175556745744, 240937075998869056, 910964509740273664, 49676441991516395584, 719170624451273114176
Offset: 1

Views

Author

N. J. A. Sloane, May 04 2000

Keywords

References

  • V. A. Liskovets and R. Poeschel, Non-Cayley-isomorphic self-complementary circulant graphs, J. Graph Th., 34, 2000, 128-141.

Links

Crossrefs

Cf. A038785, A038787.

Formula

a(p^2) = A049309(p)^2.
a(p^2) = A054246(p^2) for p=4k-1.
a(p^2) = ( (1/(p-1)) * Sum_{r|p-1 and r even} phi(r) * 2^((p-1)/r) )^2. - Sean A. Irvine, Feb 14 2021

Extensions

More terms from Valery A. Liskovets, May 09 2001
More terms and offset corrected by Sean A. Irvine, Feb 14 2021

A054930 Number of complementary pairs of circulant digraphs on n nodes.

Original entry on oeis.org

1, 1, 2, 3, 4, 10, 8, 23, 27, 70, 56, 312, 180, 700, 1096, 2131, 2068, 11020, 7316, 34008, 44232, 104968, 95420, 531296, 419654, 1398500, 1864674, 5638352, 4794088, 33597760, 17896832
Offset: 1

Views

Author

N. J. A. Sloane, May 24 2000

Keywords

Links

Crossrefs

Cf. A049297, A049309, A054929.

Formula

Average of A049297 and A049309.
a(2*n) = A049297(2*n)/2; a(2*n-1) = (A049297(2*n-1) + A049309(n))/2. - Andrew Howroyd, Jan 16 2022

Extensions

a(12)-a(31) added by Andrew Howroyd, Jan 16 2022
Showing 1-3 of 3 results.

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

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