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A104421
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Numbers n such that n, prime(n), prime(n)+n, prime(n)-n and prime(n)*n all numbers without the digit 1.
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2
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74, 75, 80, 86, 87, 95, 96, 350, 352, 354, 355, 357, 360, 364, 376, 536, 557, 564, 583, 584, 590, 592, 593, 594, 596, 599, 600, 623, 635, 639, 656, 659, 660, 665, 667, 674, 677, 678, 699, 700, 703, 706, 707, 724, 728, 734, 744, 750, 759, 762, 765, 766, 770
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OFFSET
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1,1
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COMMENTS
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The graph is of quasi-piecewise linear character.
Any other reasonable function(s) of p and m not having digit 1?
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LINKS
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EXAMPLE
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For n = 74, p = prime(74) = 373, p + n = 447, p - n = 299, p*n = 27602.
For n = 256709, p = prime(256709) = 3599737, p + n = 3856446, p - n = 3343028, p*n = 924084885533.
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MATHEMATICA
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id[x_]:=IntegerDigits[x]; pr[i_]:=Prime[i]; ra=Range[3000]; A104421=Select[ra, Position[Union[id[ # ], id[pr[ # ]], id[pr[ # ]+# ], id[pr[ # ]-# ], id[pr[ # ]*# ]], 1]=={}&]
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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