login
a(n) = sum of the exponents in the prime factorization of LCM{1,3,6,...,C(n+1,2)}.
0

%I #19 Sep 29 2024 08:56:33

%S 0,1,2,3,3,4,5,6,6,7,7,8,8,8,9,10,10,11,11,11,11,12,12,13,13,14,14,15,

%T 15,16,17,17,17,17,17,18,18,18,18,19,19,20,20,20,20,21,21,22,22,22,22,

%U 23,23,23,23,23,23,24,24,25,25,25,26,26,26,27,27,27,27,28,28,29,29,29,29,29,29,30

%N a(n) = sum of the exponents in the prime factorization of LCM{1,3,6,...,C(n+1,2)}.

%H <a href="/index/Lc#lcm">Index entries for sequences related to lcm's</a>

%F a(n) = A001222(A025555(n)). - _Sean A. Irvine_, Sep 06 2019

%F a(n) = A025528(n+1)-1. - _Pontus von Brömssen_, Sep 28 2024

%o (PARI) a025555(n) = my(s=1); for(k=1, n, s=lcm(s, k*(k+1)/2)); s \\ after _Edward Jiang_ in A025555

%o a(n) = bigomega(a025555(n)) \\ _Felix Fröhlich_, Sep 06 2019

%Y Cf. A001222, A025528, A025555.

%K nonn

%O 1,3

%A _Clark Kimberling_

%E More terms from _Sean A. Irvine_, Sep 06 2019