A242806 Integers k such that each of k, k+1, k+2, k+4, k+5, k+6 is the squarefree product of four primes.

9743613, 9780589, 22669381, 23209809, 23395137, 26143197, 28042877, 38110029, 43335609, 45127905, 45559613, 47163489, 47944865, 48030229, 48611913, 48762829, 50015301, 50600341, 50742501, 51256541, 52691613

Offset: 1

Author

Daniel Constantin Mayer, May 23 2014

Keywords

• nonn
• more

Comments

This is a higher analog to A242804 and A242805.

Examples

			9743613=3*11*503*587, 9743614=2*59*71*1163, 9743615= 5*7*167*1667, 9743617=13*37*47*431, 9743618=2*17*19*15083, 9743619=3*83*109*359.
		

Crossrefs

Cf. A242793 and A242804 (two primes), A242805 (three primes), A242829 (five primes).

Programs

Mathematica

sfp4Q[n_]:=With[{c=n+{0,1,2,4,5,6}},Union[PrimeNu[c]]=={4}&&AllTrue[c,SquareFreeQ]]; Select[Range[52700000],sfp4Q] (* Harvey P. Dale, Jul 11 2025 *)

PARI

{ default(primelimit, 1000M); i=0; j=0; k=0; l=0; m=0; loc=0; lb=2; ub=9*10^9; o=4; for(n=lb, ub, if(issquarefree(n)&&(o==omega(n)), loc=loc+1; if(1==loc, i=n; ); if(2==loc, if(i+1==n, j=n; ); if(i+1