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A133725 a(n) = Sum_{d|n} mu(n/d)*d*(3*d - 1)/2. 1
1, 4, 11, 17, 34, 35, 69, 70, 105, 106, 175, 142, 246, 213, 284, 284, 424, 321, 531, 428, 570, 535, 781, 572, 890, 750, 963, 858, 1246, 860, 1425, 1144, 1430, 1288, 1716, 1290, 2034, 1611, 2004, 1720, 2500, 1722, 2751, 2150, 2580, 2365, 3289, 2296, 3507, 2690 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Previous name was: A054525 * A000326.
LINKS
FORMULA
Möbius transform of the pentagonal numbers.
G.f.: Sum_{k>=1} mu(k) * x^k * (1 + 2*x^k) / (1 - x^k)^3. - Ilya Gutkovskiy, Sep 17 2021
EXAMPLE
a(4) = 17 = (0, -1, 0, 1) dot (1, 5, 12, 22) = (0, -5, 0, 22).
MAPLE
read("transforms") : A000326 := proc(n) n*(3*n-1)/2 ; end: a000326 := [seq(A000326(n), n=1..300)] ; a133725 := MOBIUS(a000326) ; for i from 1 to nops(a133725) do printf("%d, ", op(i, a133725)) ; od: # R. J. Mathar, Jan 19 2009
CROSSREFS
Sequence in context: A063237 A026381 A063556 * A050395 A368424 A059771
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Sep 21 2007
EXTENSIONS
More terms from R. J. Mathar, Jan 19 2009
New name from Ilya Gutkovskiy, Sep 17 2021
STATUS
approved

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Last modified March 3 03:04 EST 2024. Contains 370499 sequences. (Running on oeis4.)