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A104420
Numbers n such that n, p[n], p[n]+n, p[n]-n and p[n]*n all are 9-less.
2
1, 2, 3, 4, 5, 11, 13, 15, 26, 27, 33, 36, 48, 51, 55, 60, 61, 65, 71, 83, 100, 101, 106, 112, 115, 116, 117, 123, 126, 151, 170, 173, 177, 200, 203, 206, 216, 221, 225, 230, 231, 233, 234, 235, 240, 241, 253, 255, 271, 275, 281, 283, 284, 286, 287
OFFSET
1,2
COMMENTS
n, p[n], p[n]+n, p[n]-n and p[n]*n all are 0-less gives A104419.
LINKS
MATHEMATICA
id[x_]:=IntegerDigits[x]; pr[i_]:=Prime[i]; ra=Range[300]; A104420=Select[ra, Last[Union[id[ # ], id[pr[ # ]], id[pr[ # ]+# ], id[pr[ # ]-# ], id[pr[ # ]*# ]]]!=9&]
nlsQ[n_]:=Module[{p=Prime[n]}, Max[DigitCount[{n, p, p+n, p-n, p*n}, 10, 9]] == 0]; Select[Range[300], nlsQ] (* Harvey P. Dale, Oct 14 2019 *)
CROSSREFS
Cf. A104419.
Sequence in context: A214653 A234142 A116068 * A188532 A181288 A255260
KEYWORD
nonn,base
AUTHOR
Zak Seidov, Mar 07 2005
STATUS
approved