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a(n) = A019565(n-th prime).
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%I #10 Sep 13 2015 22:09:45

%S 3,6,10,30,42,70,22,66,330,770,2310,130,182,546,2730,1430,6006,10010,

%T 102,510,238,3570,1122,2618,442,2210,6630,9282,15470,4862,510510,114,

%U 266,798,2090,6270,14630,1482,7410,17290,16302,27170,570570,646,3230

%N a(n) = A019565(n-th prime).

%e The 5th prime is 11 (decimal), which is 1011 in binary. So a(5) is the product of the primes corresponding to the 1's of 1011, 2*3*7 = 42.

%t Table[m = 1; o = 1; k1 = Prime[k]; While[k1 > 0, k2 = Mod[k1, 2]; If[k2 == 1, m = m*Prime[o]]; k1 = (k1 - k2)/2; o = o + 1]; m, {k, 1, 55}] (* _Stefan Steinerberger_, Mar 19 2006 *)

%Y Cf. A019565.

%K nonn

%O 1,1

%A _Leroy Quet_, Aug 18 2005

%E More terms from _Stefan Steinerberger_, Mar 19 2006