OFFSET
1,2
COMMENTS
This sequence establishes a bijection between the natural numbers and A182318.
Records: 1, 3, 5, 27, 243, 7625597484987, 38127987424935, 53379182394909, 7450580596923828125, 22351741790771484375, ..., .
Records appear at: 1, 2, 3, 4, 8, 16, 48, 80, 81, 162, 256, 768, 1280, 1792, 2304, 6400, 6561, 13122, 26244, ..., . Robert G. Wilson v, Dec 14 2016
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..10000
EXAMPLE
a(6) = a(2*3) = 3*5 = 15
a(16) = a(2^(2^2)) = 3^(3^3) = 7625597484987
MATHEMATICA
a[n_] := Block[{fi = FactorInteger@ n}, Times @@ (NextPrime[#[[1]]]^a[#[[2]]] & /@ fi)]; a[1] = 1; Array[a, 60] (* Robert G. Wilson v, Dec 14 2016 *)
PROG
(PARI) a(n) = my (f=factor(n)); return (prod(i=1, #f~, nextprime(1+f[i, 1])^a(f[i, 2])))
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Rémy Sigrist, Dec 13 2016
STATUS
approved