|
| |
|
|
A077622
|
|
Number of numbers <= prime(n)# having n prime factors (with multiplicity), where prime(n)# = A002110(n) is the n-th primorial.
|
|
3
| |
|
|
1, 2, 7, 27, 190, 1621, 17271, 200536, 2757881, 47108763, 843069901, 17797435824
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
COMMENTS
| a(n) = A077618(A002110(n)), see A077621.
|
|
|
EXAMPLE
| a(3)=7, as there are 7 numbers <= prime(3)# = 2*3*5 = 30 having 3 prime factors: 8=2*2*2, 12=2*2*3, 18=2*3*3, 20=2*2*5, 27=3*3*3, 28=2*2*7 and 30=2*3*5.
|
|
|
CROSSREFS
| Cf. A001222.
Sequence in context: A150645 A060017 A058800 * A137108 A099815 A123363
Adjacent sequences: A077619 A077620 A077621 * A077623 A077624 A077625
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Nov 12 2002
|
|
|
EXTENSIONS
| 17271 from Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Jan 04 2003
a(8)-a(11) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 15 2009
a(12) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Jul 16 2011
|
| |
|
|
