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.

Previous Showing 21-27 of 27 results.

A084666 Lunar primes that are also rational primes.

Original entry on oeis.org

19, 29, 59, 79, 89, 97, 109, 409, 419, 439, 509, 619, 659, 709, 719, 739, 769, 809, 829, 839, 859, 907, 919, 929, 937, 947, 967, 1009, 1019, 1039, 1049, 1069, 1091, 1093, 1097, 1109, 1409, 1609, 1709, 1901, 1907, 2029, 2039, 2069, 2089, 2099, 2129, 2179, 2309
Offset: 1

Views

Author

N. J. A. Sloane, Nov 08 2003

Keywords

Crossrefs

Intersection of A000040 and A087097.

A088475 Numbers n such that the lunar sum of the distinct lunar prime divisors of n is >= n.

Original entry on oeis.org

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, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75
Offset: 1

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Author

David Applegate, Nov 11 2003

Keywords

Examples

			The only lunar prime that divides 10 is 90: 90*1 = 10 (cf. A087061, A087062, A087097) and 90 >= 10, so 10 is a member. - _N. J. A. Sloane_, Mar 04 2007, corrected Oct 07 2010.
		

Crossrefs

Complement is A088472, which starts 1, 2, 3, 4, 5, 6, 7, 8, 9, 100, 110, 112, ...

Extensions

Definition made more precise by Marc LeBrun, Mar 04 2007

A088479 Numbers n such that the lunar product of the distinct lunar prime divisors of n is equal to n.

Original entry on oeis.org

9, 19, 29, 39, 49, 59, 69, 79, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 109, 129, 139, 149, 159, 169, 179, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 209, 219, 239, 249, 259, 269, 279, 289, 290, 291, 292, 293, 294, 295, 296, 297
Offset: 1

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Author

David Applegate, Nov 11 2003

Keywords

Comments

Includes the unit 9, the primes A087097, products of two distinct primes, etc. - N. J. A. Sloane, May 28 2011.

Crossrefs

Cf. A087097.

A109752 Using the lunar product (see A087062 for definition), numbers n such that if n divides a*b, then n must divide either a or b. The multiplicative identity, 9, is excluded by convention.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 90
Offset: 1

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Author

David Wasserman, Aug 11 2005

Keywords

Comments

This condition is one of the definitions of a prime, so these numbers could be called lunar primes (cf. A087097).

Examples

			90 is a member because the lunar multiples of 90 are the same as the numbers ending with a 0 and if neither a nor b ends in 0, then neither does a*b.
		

Crossrefs

A151360 Lunar sum of n-th lunar prime and 9.

Original entry on oeis.org

19, 29, 39, 49, 59, 69, 79, 89, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 109, 209, 219, 309, 319, 329, 409, 419, 429, 439, 509, 519, 529, 539, 549, 609, 619, 629, 639, 649, 659, 709, 719, 729, 739, 749, 759, 769, 809, 819, 829, 839, 849, 859, 869, 879, 909, 909, 909, 909, 909, 909, 909, 909, 909, 919, 919, 919, 919, 919, 919, 919, 919, 929, 929, 929, 929, 929, 929, 929, 939, 939, 939, 939, 939, 939, 949, 949, 949, 949, 949, 959, 959, 959, 959, 969, 969, 969, 979, 979, 989
Offset: 1

Views

Author

N. J. A. Sloane, Aug 28 2010

Keywords

Comments

This is the lunar equivalent of A008864 (primes + 1).

Crossrefs

Cf. A087097.

A171816 Smallest number of rank n in the poset of lunar numbers.

Original entry on oeis.org

9, 8, 7, 6, 5, 4, 3, 2, 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000, 10000000000, 100000000000, 1000000000000, 10000000000000, 100000000000000, 1000000000000000, 10000000000000000, 100000000000000000, 1000000000000000000, 10000000000000000000
Offset: 0

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Author

Keywords

Comments

We have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing. - N. J. A. Sloane, Aug 06 2014

Crossrefs

Cf. A087061 (definition of lunar sum and product), A087062 (table of lunar product), A087097 (lunar (formerly dismal) primes).

Extensions

Edited by M. F. Hasler, Nov 12 2017

A235641 Number of n-digit lunar primes obtained by promoting the binary templates.

Original entry on oeis.org

0, 18, 81, 1539, 17661, 135489
Offset: 1

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Author

Arkadiusz Wesolowski, Apr 20 2014

Keywords

Crossrefs

Previous Showing 21-27 of 27 results.