|
Search: id:A129919
|
|
|
| A129919 |
|
a(n) is the smallest prime of the form b*prime(n+1) + prime(n) with b > 0. |
|
+0
2
|
|
| 5, 13, 19, 29, 37, 47, 131, 157, 139, 277, 179, 283, 127, 137, 577, 643, 181, 463, 919, 509, 389, 577, 439, 283, 1511, 307, 317, 761, 787, 367, 389, 953, 971, 1033, 3169, 1093, 809, 1499, 859, 3037, 541, 563, 577, 587, 1789, 2309, 1103, 677, 1601, 1627
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Dirichlet's theorem ensures that there always exists such a smallest prime because two primes are always coprime.
|
|
EXAMPLE
|
a(2) is the smallest prime of the form 5*b+3 and b > 0. Hence a(2) = 13.
|
|
MAPLE
|
a[n_] := Module[{k}, k = 1; While[Not[PrimeQ[k*Prime[n + 1] + Prime[n]]], k++ ]; k*Prime[n + 1] + Prime[n]]; Table[a[i], {i, 1, 50}]
|
|
CROSSREFS
|
Sequence in context: A084442 A023270 A103804 this_sequence A045454 A166575 A002540
Adjacent sequences: A129916 A129917 A129918 this_sequence A129920 A129921 A129922
|
|
KEYWORD
|
nonn,less
|
|
AUTHOR
|
J. M. Bergot (thekingfishb(AT)yahoo.ca), Jun 05 2007
|
|
EXTENSIONS
|
Edited and extended by Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jul 16 2007
|
|
|
Search completed in 0.002 seconds
|
