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A172155 a(n) = Omega(6*n-1)*Omega(6*n+1). 1
1, 1, 1, 2, 1, 2, 1, 2, 2, 1, 2, 1, 2, 2, 2, 2, 1, 1, 2, 4, 3, 2, 1, 4, 1, 2, 2, 2, 3, 1, 4, 1, 1, 4, 2, 4, 2, 1, 2, 1, 6, 2, 2, 2, 1, 3, 1, 4, 2, 4, 2, 1, 2, 6, 2, 2, 6, 1, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 4, 1, 6, 1, 2, 2, 2, 3, 1, 2, 6, 2, 2, 2, 2, 2, 2, 4, 1, 4, 4, 3, 2, 4, 2, 2, 1, 3, 4, 2, 3, 1, 3, 2, 1, 8, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,4
LINKS
EXAMPLE
For n=1, Omega(6*n-1)*Omega(6*n+1)=Omega(5)*Omega(7)=1, so a(1)=1.
MAPLE
A172155 := proc(n) numtheory[bigomega](6*n-1)*numtheory[bigomega](6*n+1) ; end proc: seq(A172155(n), n=1..100) ; # R. J. Mathar, Jan 30 2010
MATHEMATICA
Table[Times@@PrimeOmega[6*n+{1, -1}], {n, 120}] (* Harvey P. Dale, Jul 16 2020 *)
CROSSREFS
Cf. A145193.
Sequence in context: A080763 A245920 A165413 * A080573 A186440 A006340
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected by R. J. Mathar, Jan 30 2010
STATUS
approved

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Last modified June 19 03:10 EDT 2024. Contains 373492 sequences. (Running on oeis4.)