A085709 - OEIS

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A085709

a(0)=1; then smallest multiple of n such that a(n) + a(n-1) is a semiprime.

%I #10 Dec 15 2017 17:36:27

%S 1,3,6,3,12,10,12,14,8,18,20,66

%N a(0)=1; then smallest multiple of n such that a(n) + a(n-1) is a semiprime.

%e a(12) does not exist, since 66+12k = 2*3*(2k+11) is not a semiprime for any positive k.

%Y Cf. A001358.

%K fini,full,nonn

%O 0,2

%A _Jason Earls_ and _Amarnath Murthy_, Jul 19 2003

%E Edited by _Dean Hickerson_, Jul 19 2003