A158282 Composite numbers k such that prime = abs(smallest digit of k - sum of all the other digits of k).

14, 16, 18, 20, 24, 25, 27, 30, 35, 36, 38, 42, 46, 49, 50, 52, 57, 58, 63, 64, 68, 69, 70, 72, 74, 75, 81, 85, 86, 92, 94, 96, 102, 104, 106, 110, 112, 115, 117, 120, 121, 122, 124, 126, 133, 135, 140, 142, 144, 148, 153, 159, 160, 162, 166, 168, 171, 175, 177, 184

Offset: 1

Author

Juri-Stepan Gerasimov, Mar 15 2009, May 25 2009

Keywords

• nonn
• base

Examples

			14(3=abs(1-4)), 16(5=abs(1-6)), 18(7=abs(1-8)), 20(2=2-0)
		

Crossrefs

Cf. A000040, A002808, A156979.

Programs

Mathematica

sdkQ[n_]:=Module[{id=IntegerDigits[n],mid},mid=Min[id];PrimeQ[Abs[mid-Total[DeleteCases[ id,mid,1,1]]]]]; cnkQ[n_]:=CompositeQ[n]&&sdkQ[n]; Select[Range[200],cnkQ] (* Harvey P. Dale, Aug 23 2024 *)

Extensions

Entries checked by R. J. Mathar, May 19 2010