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A167329
Totally multiplicative sequence with a(p) = 10*(p+3) for prime p.
1
1, 50, 60, 2500, 80, 3000, 100, 125000, 3600, 4000, 140, 150000, 160, 5000, 4800, 6250000, 200, 180000, 220, 200000, 6000, 7000, 260, 7500000, 6400, 8000, 216000, 250000, 320, 240000, 340, 312500000, 8400, 10000, 8000, 9000000, 400, 11000, 9600, 10000000, 440, 300000
OFFSET
1,2
LINKS
FORMULA
Multiplicative with a(p^e) = (10*(p+3))^e. If n = Product p(k)^e(k) then a(n) = Product (10*(p(k)+3))^e(k).
a(n) = A165831(n) * A166591(n) = 10^bigomega(n) * A166591(n) = 10^A001222(n) * A166591(n).
MATHEMATICA
a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((fi[[All, 1]] + 3)^fi[[All, 2]])); Table[a[n]*10^PrimeOmega[n], {n, 1, 100}] (* G. C. Greubel, Jun 09 2016 *)
f[p_, e_] := (10*(p+3))^e; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Oct 21 2023 *)
CROSSREFS
KEYWORD
nonn,easy,mult
AUTHOR
Jaroslav Krizek, Nov 01 2009
STATUS
approved