A083202 - OEIS

%I #13 Oct 26 2019 16:36:53

%S 1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,1,7,1,3,15,15,1,2,1,1,10,10,92,1,1,2,1,

%T 1,1,1,6,6,2,2,57,1,1,15,3,2,2,2,5,3,6,1,1,1,1,1,1,1,3,1,1,1,4,12,69,

%U 69,6,186,30,1,1,1,1,1,1,1,1,1,1,11,1,1,1

%N a(n) = gcd(A000055(n), A000055(n+1)).

%H Alois P. Heinz, <a href="/A083202/b083202.txt">Table of n, a(n) for n = 0..1000</a>

%e A000055(6)=6, A000055(7)=11, so a(6) = gcd(6,11) = 1.

%o (PARI) {v=[1, 1, 1, 1, 2, 3, 6, 11, 23, 47, 106, 235, 551, 1301, 3159, 7741, 19320, 4 8629, 123867, 317955, 823065, 2144505, 5623756, 14828074, 39299897, 104636890, 2 79793450, 751065460, 2023443032, 5469566585, 14830871802, 40330829030, 109972410] for (i=1,length(v)-1,print1(gcd(v[i],v[i+1])","))}

%Y Cf. A000055.

%K nonn

%O 0,6

%A _Jon Perry_, Jun 01 2003

%E More terms from _Alois P. Heinz_, Sep 26 2011