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%I #5 May 29 2014 16:01:06
%S 1,4,6,7,9,10,11,18,19,23,27,29,30,32,40,41,42,43,44,49,60,61,63,67,
%T 69,70,73,74,79,80,110,111,131,140,143,144,166,170,171,179,180,181,
%U 183,184,187,189,193,196,199,200,201,202,206,209,223,228,229,233,261,263,270
%N Numbers n such that n, p[n], p[n]+n, p[n]-n and p[n]*n all are 5-less.
%C From the first 3000 primes, only 369 are such that n, p[n], p[n]+n, p[n]-n and p[n]*n all are 5-less.
%t id[x_]:=IntegerDigits[x];pr[i_]:=Prime[i];ra=Range[3000];A104425=Select[ra, Position[Union[id[ # ], id[pr[ # ]], id[pr[ # ]+# ], id[pr[ # ]-# ], id[pr[ # ]*# ]], 5]=={}&]
%t flQ[n_]:=Module[{pr=Prime[n]},Union[DigitCount[{n,pr,pr+n,pr-n,pr*n},10,5]] == {0}]; Select[Range[300],flQ] (* _Harvey P. Dale_, May 29 2014 *)
%Y Cf. A104419-A104428.
%K nonn,base
%O 1,2
%A _Zak Seidov_, Mar 07 2005