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A083262
a(n) = sigma(A046523(n)), sum of divisors of the least number with the same prime signature as n.
1
1, 3, 3, 7, 3, 12, 3, 15, 7, 12, 3, 28, 3, 12, 12, 31, 3, 28, 3, 28, 12, 12, 3, 60, 7, 12, 15, 28, 3, 72, 3, 63, 12, 12, 12, 91, 3, 12, 12, 60, 3, 72, 3, 28, 28, 12, 3, 124, 7, 28, 12, 28, 3, 60, 12, 60, 12, 12, 3, 168, 3, 12, 28, 127, 12, 72, 3, 28, 12, 72, 3, 195, 3, 12, 28, 28, 12, 72
OFFSET
1,2
LINKS
MATHEMATICA
Table[DivisorSigma[1, Times @@ MapIndexed[Prime[First@ #2]^#1 &, Sort[FactorInteger[n][[All, -1]], Greater]] - Boole[n == 1]], {n, 78}] (* Michael De Vlieger, May 20 2017 *)
PROG
(PARI)
A046523(n) = my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]) \\ This function from Charles R Greathouse IV, Aug 17 2011
A083262(n) = sigma(A046523(n)); \\ Antti Karttunen, May 19 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, May 09 2003
EXTENSIONS
Name clarified by Antti Karttunen, May 19 2017
STATUS
approved