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%I #17 May 03 2017 23:56:14
%S 4,6,20,14,44,26,68,114,46,174,124,74,164,258,282,106,354,244,134,426,
%T 292,474,664,356,194,404,206,428,1526,452,762,262,1370,278,894,906,
%U 628,978,1002,346,1790,362,764,386,2364,2388,844,446,908,1374,466,2390
%N a(n) = prime(n) * (prime(n+2) - prime(n+1)).
%H Michel Marcus, <a href="/A205955/b205955.txt">Table of n, a(n) for n = 1..1000</a>
%e a(1) = prime(1)*(prime(3) - prime(2)) = 2*(5-3) = 4.
%e a(2) = prime(2)*(prime(4) - prime(3)) = 3*(7-5) = 6.
%e a(3) = prime(3)*(prime(5) - prime(4)) = 5*(11-7) = 20.
%p A205955:=n->ithprime(n)*(ithprime(n+2)-ithprime(n+1)): seq(A205955(n), n=1..100); # _Wesley Ivan Hurt_, May 02 2017
%t #1 (#3 - #2) & @@ # & /@ Partition[Prime@ Range@ 54, 3, 1] (* _Michael De Vlieger_, May 03 2017 *)
%o (PARI) a(n) = prime(n) * (prime(n+2) - prime(n+1)) \\ _Michel Marcus_, Aug 06 2013
%Y Cf. A000040, A001223.
%K nonn,easy
%O 1,1
%A _Umut Uludag_, Feb 02 2012