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A171038
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In the sequence of prime numbers, replace all the '7' digits with '4' and vice versa.
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3
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2, 3, 5, 4, 11, 13, 14, 19, 23, 29, 31, 34, 71, 73, 74, 53, 59, 61, 64, 41, 43, 49, 83, 89, 94, 101, 103, 104, 109, 113, 124, 131, 134, 139, 179, 151, 154, 163, 164, 143, 149, 181, 191, 193, 194, 199, 211, 223, 224, 229, 233, 239, 271, 251, 254, 263
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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fixp[n_]:=FromDigits[IntegerDigits[n]/.{7->a, 4->b}/.{a->4, b->7}]; fixp/@Prime[Range[100]] (* Harvey P. Dale, Apr 25 2011 *)
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PROG
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(PARI) a(n)=my(v=[0, 1, 2, 3, 7, 5, 6, 4, 8, 9]); subst(Pol(apply(k->v[k+1], digits(prime(n)))), 'x, 10) \\ Charles R Greathouse IV, Jul 25 2013
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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