|
|
|
|
1, 2, 6, 10, 14, 18, 30, 34, 38, 42, 46, 50, 58, 66, 78, 86, 90, 94, 98, 106, 118, 130, 134, 150, 154, 170, 174, 186, 190, 198, 206, 214, 218, 226, 234, 254, 258, 266, 270, 274, 286, 294, 310, 314, 318, 326, 338, 350, 354, 366, 370, 394, 398, 406, 410, 426
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
Numbers k such that the number of distinct prime divisors of k is equal to the number of distinct prime divisors of the pentagonal number k*(3*k-1)/2.
|
|
LINKS
|
|
|
MATHEMATICA
|
Select[Range[100], PrimeNu[#] == PrimeNu[#*(3*# - 1)/2] &] (* G. C. Greubel, Apr 23 2017 *)
|
|
PROG
|
(PARI) select(k->omega(k)==omega(k*(3*k-1)/2), vector(500, k, k))
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|