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%I #3 Mar 30 2012 17:26:11
%S 1,2,3,5,10,11,13,23,24,29,30,32,35,38,43,46,51,60,62,81,82,98,100,
%T 140,146,180,185,188,189,190,191,200,202,205,209,215,221,226,231,246,
%U 252,254,255,261,266,281,282,291,293,301,320,321,323,346,369,381,382,391
%N Numbers n such that n, p[n], p[n]+n, p[n]-n and p[n]*n all are 7-less.
%C From the first 3000 primes, only 200 are such that n, p[n], p[n]+n, p[n]-n and p[n]*n all are 7-less.
%t id[x_]:=IntegerDigits[x];pr[i_]:=Prime[i];ra=Range[3000];A104427=Select[ra, Position[Union[id[ # ], id[pr[ # ]], id[pr[ # ]+# ], id[pr[ # ]-# ], id[pr[ # ]*# ]], 7]=={}&]
%Y Cf. A104419-A104428.
%K nonn,base
%O 1,2
%A _Zak Seidov_, Mar 07 2005