A174244 Least of 4 consecutive integers such that their product +-5 are primes.

1, 11, 31, 61, 116, 131, 321, 336, 906, 1081, 1101, 1216, 1601, 1821, 2081, 2106, 2356, 2491, 3051, 3101, 3281, 3286, 3496, 3736, 4576, 4716, 4861, 4876, 4886, 4981, 5066, 5096, 5301, 5881, 6066, 6121, 6401, 6761, 6916, 7061, 7446, 7556, 8021, 8041, 8056

Offset

1,2

Comments

1*2*3*4=24+-5 -> primes,..

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

f1[n_]:=PrimeQ[n-5]&&PrimeQ[n+5]; f2[n_]:=n*(n+1)*(n+2)*(n+3); lst={}; Do[If[f1[f2[n]], AppendTo[lst, n]], {n, 8!}]; lst
Select[Partition[Range[8200], 4, 1], AllTrue[Times@@#+{5, -5}, PrimeQ]&][[All, 1]] (* or *) Select[ Range[ 8200], AllTrue[6#+11#^2+6#^3+#^4+{5, -5}, PrimeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 20 2021 *)

Crossrefs

Cf. A014574, A174242, A174243.

Sequence in context: A125239 A062786 A090562 * A136061 A296034 A090233

Adjacent sequences: A174241 A174242 A174243 * A174245 A174246 A174247

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, Mar 13 2010

Status

approved