A316113 - OEIS

%I #19 Oct 08 2018 15:27:44

%S 1,4,9,10,20,11,35,22,30,22,66,22,91,37,28,46,119,32,152,31,41,68,184,

%T 37,110,106,93,53,261,51,279,94,69,121,59,60,370,192,97,64,451,54,430,

%U 94,65,186,517,74,259,112,122,97,583,95,92,92,158,263,767,77,671

%N a(n) is the least sum of a tuple containing n as an element where the denominator of the sum of reciprocals isn't divisible by any of the prime factors of n.

%H Ray Chandler, <a href="/A316113/b316113.txt">Table of n, a(n) for n = 1..100</a>

%e a(12) = 22 because the tuple [3, 3, 4, 12] has the sum of reciprocals 1/3 + 1/3 + 1/4 + 1/12 = 1 of which the denominator is 1 and has no common prime factors with n = 12.

%e a(25) = 110 because the tuple [5, 5, 25, 25, 50] has the sum of reciprocals 1/5 + 1/5 + 1/25 + 1/25 + 1/50 = 1/2 of which the denominator is 2 and has no common prime factors with n = 25.

%Y Cf. A051908, A201644, A201646, A201647, A201648, A201649.

%K nonn

%O 1,2

%A _David A. Corneth_, Jul 22 2018

%E More terms from _Ray Chandler_, Oct 02 2018