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A104421 Numbers n such that n, prime(n), prime(n)+n, prime(n)-n and prime(n)*n all numbers without the digit 1. 2

%I #11 Dec 06 2013 12:10:48

%S 74,75,80,86,87,95,96,350,352,354,355,357,360,364,376,536,557,564,583,

%T 584,590,592,593,594,596,599,600,623,635,639,656,659,660,665,667,674,

%U 677,678,699,700,703,706,707,724,728,734,744,750,759,762,765,766,770

%N Numbers n such that n, prime(n), prime(n)+n, prime(n)-n and prime(n)*n all numbers without the digit 1.

%C The graph is of quasi-piecewise linear character.

%C Any other reasonable function(s) of p and m not having digit 1?

%C Subsequence of A084368: a(1) = 75 = A084368(36), a(100) = 2744 = A084368(898). - _Zak Seidov_, Dec 04 2013

%H Zak Seidov, <a href="/A104421/b104421.txt">Table of n, a(n) for n = 1..3000</a>

%e For n = 74, p = prime(74) = 373, p + n = 447, p - n = 299, p*n = 27602.

%e For n = 256709, p = prime(256709) = 3599737, p + n = 3856446, p - n = 3343028, p*n = 924084885533.

%t 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]=={}&]

%Y Cf. A038603, A084368, A104419-A104428.

%K nonn,base

%O 1,1

%A _Zak Seidov_, Mar 07 2005

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Last modified April 25 11:39 EDT 2024. Contains 371969 sequences. (Running on oeis4.)