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a(n) = A019565(n) - 1.
12

%I #7 Dec 19 2020 05:47:25

%S 0,1,2,5,4,9,14,29,6,13,20,41,34,69,104,209,10,21,32,65,54,109,164,

%T 329,76,153,230,461,384,769,1154,2309,12,25,38,77,64,129,194,389,90,

%U 181,272,545,454,909,1364,2729,142,285,428,857,714,1429,2144,4289,1000,2001,3002,6005,5004,10009,15014,30029,16,33,50

%N a(n) = A019565(n) - 1.

%H Antti Karttunen, <a href="/A339809/b339809.txt">Table of n, a(n) for n = 0..8192</a>

%o (PARI)

%o A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };

%o A339809(n) = (A019565(n)-1);

%Y Cf. A019565, A339810, A339811, A339812.

%Y Cf. also A339820, A339821.

%K nonn

%O 0,3

%A _Antti Karttunen_, Dec 18 2020