|
| |
|
|
A074822
|
|
Primes p(n) such that p(n) + 4 = p(n+1) and p(n) == 9 (mod 10).
|
|
15
| |
|
|
19, 79, 109, 229, 349, 379, 439, 499, 739, 769, 859, 1009, 1279, 1429, 1489, 1549, 1579, 1609, 1999, 2239, 2269, 2389, 2539, 2659, 2689, 2749, 3019, 3079, 3319, 3529, 3919, 4129, 4519, 4639, 4729, 4789, 4969, 4999, 5479, 5569, 5689, 5779, 5839, 6199
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Also primes for which k is equal to 5 in A117078. Examples: prime(9) = prime(8) + (prime(8) mod 5) = 19 + (19 mod 5)=23; prime(23) = prime(22) + (prime(22) mod 5) = 79 + (79 mod 5)=83; prime(1359) = prime(1358) + (prime(1358) mod 5) = 11239+ (11239 mod 5)=11243 - Remi Eismann (reismann(AT)free.fr), May 14 2006
The prime numbers in this sequence are of the form (10i-1) with i=(level(n)+1)/2, level(n) defined in A117563. - Remi Eismann (reismann(AT)free.fr), May 14 2006, May 04 2007
Consider A117078: a(n) = smallest k such that prime(n+1) = prime(n) + (prime(n) mod k), or 0 if no such k exists. Sequence gives values of prime(n) for which k=5. - Remi Eismann (reismann(AT)free.fr), May 14 2006
|
|
|
LINKS
| Remi Eismann, Table of n, a(n) for n = 1..10000
|
|
|
MATHEMATICA
| Prime[ Select[ Range[1000], Prime[ # ] + 4 == Prime[ # + 1] && Mod[ Prime[ # ], 10] == 9 & ]]
Transpose[Select[Partition[Prime[Range[820]], 2, 1], Last[#]-First[#] == 4&&Mod[First[#], 10]==9&]][[1]] (* From Harvey P. Dale, Oct 20 2011 *)
|
|
|
CROSSREFS
| Cf. A117078, A074822, A001223, A117563, A001359, A118359, A118922, A118924, A119504.
Sequence in context: A098467 A041700 A132234 * A139871 A142789 A158491
Adjacent sequences: A074819 A074820 A074821 * A074823 A074824 A074825
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Sep 30 2002
|
|
|
EXTENSIONS
| Edited by Robert G. Wilson v (rgwv(AT)rgwv.com) and N. J. A. Sloane (njas(AT)research.att.com), Oct 03 2002
Entry revised by N. J. A. Sloane (njas(AT)research.att.com), Feb 24 2007
|
| |
|
|
