A166011 -id:A166011 - cp's OEIS frontend

A166010 a(n) = prime(n)^2-4.

0, 5, 21, 45, 117, 165, 285, 357, 525, 837, 957, 1365, 1677, 1845, 2205, 2805, 3477, 3717, 4485, 5037, 5325, 6237, 6885, 7917, 9405, 10197, 10605, 11445, 11877, 12765, 16125, 17157, 18765, 19317, 22197, 22797, 24645, 26565, 27885, 29925, 32037

Offset: 1

Vladimir Joseph Stephan Orlovsky, Oct 04 2009

Least common multiple of prime(n)-2 and prime(n)+2.

G. C. Greubel, Table of n, a(n) for n = 1..10000

Cf. A066830, A084921, A166011.

Cf. A049001, A084920, A182200; A182174.

[NthPrime(n)^2-4: n in [1..41]]; // Bruno Berselli, Apr 17 2012

f[n_]:=LCM[n-2,n+2]; lst={};Do[p=Prime[n];AppendTo[lst,f[p]],{n,5!}]; lst
Prime[Range[5!]]^2 - 4 (* Zak Seidov, Apr 17 2012 *)

a(n)=prime(n)^2-4 \\ Charles R Greathouse IV, Apr 17 2012

a(n) = A001248(n)-4 = A040976(n)*A052147(n). [Bruno Berselli, Apr 17 2012]

Definition rewritten by Bruno Berselli, Apr 17 2012

A222963 a(n) = (p-3)*(p+3)/4 where p is the n-th prime.

Original entry on oeis.org

0, 4, 10, 28, 40, 70, 88, 130, 208, 238, 340, 418, 460, 550, 700, 868, 928, 1120, 1258, 1330, 1558, 1720, 1978, 2350, 2548, 2650, 2860, 2968, 3190, 4030, 4288, 4690, 4828, 5548, 5698, 6160, 6640, 6970, 7480, 8008, 8188

Offset: 2

Vincenzo Librandi, Apr 05 2013

Old name was: Numbers n such that sqrt(4*n+9) is prime.

Vincenzo Librandi, Table of n, a(n) for n = 2..1000

Subsequence of A028552.

Cf. A000040, A001248, A005097, A168669.

[(p^2-9)/4: p in PrimesInInterval(3, 200)];

Select[Range[0, 10000], PrimeQ[Sqrt[4 # + 9]]&]

4*a(n)+9 = A001248(n).

a(n) = A166011(n)/2. - Michel Marcus, Apr 22 2016

cp's OEIS Frontend

A166010 a(n) = prime(n)^2-4.

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