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%I #13 Sep 18 2019 13:48:01
%S 14,26,38,50,62,63,64,74,86,98,110,122,123,124,134,146,158,170,174,
%T 182,183,184,194,206,215,218,230,242,243,244,254,266,278,290,302,303,
%U 304,314,326,338,342,350,362,363,364,368,374,386,398,410,422,423,424,425
%N Integers n such that there exists at least one divisor d of n, 1 < d < n, such that d divides n, d+1 divides n+1 and d+2 divides n+2.
%H Amiram Eldar, <a href="/A082773/b082773.txt">Table of n, a(n) for n = 1..10000</a>
%e 38 is in the sequence since 2 divides 38, 3 divides 39 and 4 divides 40.
%t dvsQ[n_]:=Module[{dvsrs=Rest[Most[Divisors[n]]]},Table[Divisible[n+1, dvsrs[[i]]+1] && Divisible[n+2,dvsrs[[i]]+2],{i,Length[dvsrs]}]]; Select[Range[2,450],!PrimeQ[#]&&Or@@dvsQ[#]&] (* _Harvey P. Dale_, Dec 28 2011 *)
%o for (int a = 1; a < 200; a++) for (int b = 2; b < a; b++) if ((a%b==0)&&((a+1)%(b+1)==0)&&((a+2)%(b+2)==0)) cout << a << ", "; // outputs a
%o (PARI) isok(n) = {fordiv(n, d, if ((d>1) && (d<n) && ! ((n+1) % (d+1)) && ! ((n+2) % (d+2)), return (1)););} \\ _Michel Marcus_, Sep 18 2019
%K easy,nonn
%O 1,1
%A Anne M. Donovan (anned3005(AT)aol.com), May 21 2003