|
|
A109288
|
|
Semiprimes equal to p*q + 1, where p and q are distinct primes.
|
|
3
|
|
|
15, 22, 34, 35, 39, 58, 86, 87, 94, 95, 119, 123, 134, 142, 143, 146, 159, 178, 202, 203, 206, 214, 215, 218, 219, 254, 299, 302, 303, 327, 335, 382, 394, 395, 446, 447, 454, 482, 502, 515, 527, 538, 543, 554, 566, 623, 634, 635, 695, 698, 699, 707, 718, 746
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
LINKS
|
|
|
MATHEMATICA
|
With[{nn=60}, Take[Select[Union[Times@@#+1&/@Subsets[Prime[Range[2nn]], {2}]], PrimeOmega[#]==2&], nn]] (* Harvey P. Dale, Apr 28 2018 *)
|
|
PROG
|
(PARI) for(i=1, 1000, if(bigomega(i)==2&&bigomega(i+1)==2&&issquare(i)==0, print1(i+1, ", "))) (Klasen)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
More terms from Lambert Klasen (lambert.klasen(AT)gmx.net), Aug 21 2005
|
|
STATUS
|
approved
|
|
|
|