|
| |
|
|
A160353
|
|
Numbers of the form pqr, where p<q<r are odd primes such that r = +/-1 (mod pq).
|
|
3
| |
|
|
435, 465, 861, 885, 903, 915, 1335, 1743, 2211, 2235, 2265, 2485, 2667, 2685, 2715, 3081, 3165, 3507, 3585, 3615, 4035, 4065, 4323, 4431, 4865, 4965, 5151, 5253, 5271, 5385, 5835, 5995, 6123, 6153, 6285, 6315, 6441, 6501, 6567, 6735, 7077, 7185, 7385
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Kaplan (2007) has shown that this is a subsequence of A117223 (and thus of A160350; see there for the reference), i.e. the cyclotomic polynomial Phi[n] has coefficients in {0,1,-1} for indices n listed here.
This is a subsequence of A160352 which drops the requirement p>2.
See A160350 for further details and references.
|
|
|
EXAMPLE
| a(1)=435=3*5*29 is the smallest product of odd primes p<q<r such that r is congruent to +/- 1 modulo the product of the smaller factors, p*q.
|
|
|
PROG
| (PARI) forstep( pqr=1, 9999, 2, my(f=factor(pqr)); #f~==3 & vecmax(f[, 2])==1 & abs((f[3, 1]+1)%(f[1, 1]*f[2, 1])-1)==1 & print1(pqr", "))
|
|
|
CROSSREFS
| Sequence in context: A145318 A054987 A054905 * A124043 A190828 A084293
Adjacent sequences: A160350 A160351 A160352 * A160354 A160355 A160356
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| M. F. Hasler (www.univ-ag.fr/~mhasler), May 11 2009
|
| |
|
|
