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A208768 The distinct values of A070198. 4

%I #27 Mar 13 2018 04:09:18

%S 0,1,5,11,59,419,839,2519,27719,360359,720719,12252239,232792559,

%T 5354228879,26771144399,80313433199,2329089562799,72201776446799,

%U 144403552893599,5342931457063199,219060189739591199,9419588158802421599,442720643463713815199

%N The distinct values of A070198.

%C The terms of A070198, and duplicates removed.

%C a(n) = A051451(n) - 1 = A051452(n) - 2.

%C From _Daniel Forgues_, Apr 27 2014: (Start)

%C Factorizations:

%C 5, 11, 59, 419, 839 are primes;

%C 2519 = 11*229, 27719 = 53*523, 360359 = 173*2083,

%C 720719 = 31*67*347, 12252239 = 29*647*653;

%C 232792559, 5354228879 are primes;

%C 26771144399 = 47*12907*44131, 80313433199 = 29*61*45400471;

%C 2329089562799 is prime;

%C 72201776446799 = 37*149*239*1091*50227;

%C 144403552893599 is prime;

%C Very likely contains an infinite number of primes (see A057824). (End)

%C A more natural (compare with A051452) name for the sequence: lcm(1, ..., k) - 1, where k is the n-th prime power A000961(n). - _Daniel Forgues_, May 09 2014

%H Reinhard Zumkeller, <a href="/A208768/b208768.txt">Table of n, a(n) for n = 1..250</a>

%o (Haskell)

%o import Data.List (nub)

%o a208768 n = a208768_list !! (n-1)

%o a208768_list = nub a070198_list

%K nonn

%O 1,3

%A _Reinhard Zumkeller_, Mar 01 2012

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Last modified August 14 09:16 EDT 2024. Contains 375159 sequences. (Running on oeis4.)