login
A079274
Number of divisors associated with the cyclic cases within the n-th group of least prime signatures.
1
1, 0, 3, 4, 14, 18, 65, 82, 253, 378, 953, 1460, 3667, 5480, 12917, 20582, 45130, 71970, 156510, 248020, 524446, 846962, 1733252, 2806484, 5702101, 9186010, 18375867, 29872508, 58760991, 95500008, 186871472, 302966474, 587603027, 956192230
OFFSET
0,3
FORMULA
a(n) = A074141(n) - 2* A074141(n-1) for n > 0 and a(0) = 1
EXAMPLE
The number of divisors doubles each time we create a new "matching" partition by appending "1" to a given partition. Therefore we may write
..1..0..3..4..14..18..65..82..253..378..953...
+ ...2..4.14..36.100.236.602.1368.3242.7240...
= 1..2..7.18..50.118.301.684.1621.3620.8193...
CROSSREFS
Cf. A074141.
Sequence in context: A297839 A279938 A280331 * A282421 A282684 A024863
KEYWORD
easy,nonn
AUTHOR
Alford Arnold, Feb 06 2003
EXTENSIONS
More terms from Pab Ter (pabrlos(AT)yahoo.com), May 27 2004
STATUS
approved