|
Search: id:A003959
|
|
|
| A003959 |
|
Fully multiplicative with a(p) = p+1 for prime p. |
|
+0
26
|
|
| 1, 3, 4, 9, 6, 12, 8, 27, 16, 18, 12, 36, 14, 24, 24, 81, 18, 48, 20, 54, 32, 36, 24, 108, 36, 42, 64, 72, 30, 72, 32, 243, 48, 54, 48, 144, 38, 60, 56, 162, 42, 96, 44, 108, 96, 72, 48, 324, 64, 108, 72, 126, 54, 192, 72, 216, 80, 90, 60, 216, 62, 96, 128, 729, 84, 144, 68
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=1..1000
|
|
FORMULA
|
If n = Product p(k)^e(k) then a(n) = Product (p(k)+1)^e(k).
Multiplicative with a(p^e) = (p+1)^e. - David W. Wilson (davidwwilson(AT)comcast.net), Aug 01, 2001.
|
|
PROGRAM
|
(PARI) a(n)=if(n<1, 0, direuler(p=2, n, 1/(1-X-p*X))[n]) (from R. Stephan)
|
|
CROSSREFS
|
Apart from initial terms, same as A064478. Cf. A003958.
Cf. A063441.
Adjacent sequences: A003956 A003957 A003958 this_sequence A003960 A003961 A003962
Sequence in context: A021290 A016656 A084425 this_sequence A083111 A132065 A157020
|
|
KEYWORD
|
nonn,easy,nice,mult
|
|
AUTHOR
|
Marc LeBrun (mlb(AT)well.com)
|
|
|
Search completed in 0.002 seconds
|
