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A052202 Numbers k such that the product of the logarithms of k's prime factors is greater than their sum. 1
77, 85, 91, 95, 115, 119, 121, 133, 143, 145, 155, 161, 169, 185, 187, 203, 205, 209, 215, 217, 221, 235, 245, 247, 253, 259, 265, 275, 287, 289, 295, 299, 301, 305, 319, 323, 325, 329, 335, 341, 343, 355, 357, 361, 363, 365, 371, 377, 385, 391, 395, 399 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
First even term is 1334.
Previous name was: If p^a(p,n) is highest power of p that divides n, then Product_(p=primes) [log(p)^a(p,n) ] > log(n).
From Charlie Neder, Dec 03 2018: (Start)
Primes are counted with multiplicity.
Does this sequence have asymptotic density 1?
a(100000) = 189835. (End)
LINKS
EXAMPLE
245 is included because 245 = 5*7^2 and log(5)*log(7)^2 > log(245).
MATHEMATICA
aQ[n_] := Times@@Power@@@({Log[#1], #2} & @@@FactorInteger[n]) > Log[n]; Select[Range[400], aQ] (* Amiram Eldar, Dec 03 2018 *)
PROG
(PARI) isok(n) = my(f=factor(n)); prod(k=1, #f~, log(f[k, 1])^f[k, 2]) > log(n); \\ Michel Marcus, Dec 04 2018
CROSSREFS
Sequence in context: A344799 A344800 A294741 * A089525 A274172 A061671
KEYWORD
nonn
AUTHOR
Leroy Quet, Jan 28 2000
EXTENSIONS
Title changed by Charlie Neder, Dec 04 2018
STATUS
approved

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Last modified April 24 11:16 EDT 2024. Contains 371936 sequences. (Running on oeis4.)