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%I #17 Apr 27 2020 06:30:40
%S 1,3,3,2,5,7,7,6,7,11,11,8,11,15,4,13,8,15,21,15,12,17,10,23,19,14,23,
%T 29,23,20,23,31,6,29,18,27,35,14,31,20,29,43,31,26,31,16,45,35,24,45,
%U 47,37,34,39,16,53,47,26,41,59,20,43,30,47,65,18,47,32,47,22,63,55,38,59
%N Number of numbers from 1 to A002808(n) - 1 that are non-coprime to A002808(n).
%C a(n) is the number of positive numbers k < A002808(n) with gcd(A002808(n), k) not 1.
%C a(n) gives the row length of the irregular triangle A290600.
%H Andrew Howroyd, <a href="/A290599/b290599.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A016035(A002808(n)). - _Andrew Howroyd_, Apr 26 2020
%e a(4) = 2 because A002808(4) = 9, with the two non-coprime positive numbers smaller than 9, namely 3 and 6. See row n = 4 of A290600.
%o (PARI) [k-1-eulerphi(k) | k<-[2..100], !isprime(k)] \\ _Andrew Howroyd_, Apr 26 2020
%Y Cf. A002808, A016035, A290600.
%K nonn
%O 1,2
%A _Wolfdieter Lang_, Aug 30 2017
%E Terms a(51) and beyond from _Andrew Howroyd_, Apr 26 2020
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