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A103846 Sum of the non-unitary divisors of A064115(n) (or of 1+A064115(n)). 2
96, 864, 2160, 5400, 9600, 6720, 46080, 94080, 108864, 191968, 138240, 345600, 380160, 482976, 287280, 806400, 1016064, 777600, 1814400, 3317760, 3686400, 3352320, 5491200, 5160960, 3839400, 5702400, 4976640, 7464960, 7711200, 8259840, 10108800, 12005760, 10886400 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..344 (calculated from the b-file at A064115 by Giovanni Resta)
EXAMPLE
A103846(1)=96 is the sum of the non-unitary divisors of A064115(1)=188 and also of 1+A064115(1)=189: 2+94=96 and 3+9+21+63=96.
MATHEMATICA
nusigma[1]=0; nusigma[n_] := DivisorSigma[1, n] - Times @@ (1 + Power @@@ FactorInteger[n]); seq={}; s1=0; Do[s2=nusigma[n]; If[s1>0 && s2==s1, AppendTo[seq, s1]]; s1=s2, {n, 1, 10^6}]; seq (* Amiram Eldar, Jun 10 2019 *)
CROSSREFS
Sequence in context: A326576 A202890 A173615 * A203979 A296960 A202583
KEYWORD
nonn
AUTHOR
Emeric Deutsch, Feb 17 2005
EXTENSIONS
More terms from Amiram Eldar, Jun 10 2019
STATUS
approved

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Last modified May 26 14:36 EDT 2024. Contains 372826 sequences. (Running on oeis4.)