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A107624
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Numbers n such that every digit of n and n-th prime contains a loop (only digits 0,4,6,8,9 in n and n-th prime).
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3
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80, 600, 669, 884, 4646, 4666, 4806, 4980, 6480, 6666, 6806, 6849, 8448, 8688, 9489, 9494, 40046, 40664, 40804, 49848, 64444, 64466, 68864, 68994, 69008, 69060, 69084, 69089, 69090, 69899, 440986, 440999, 444049, 444080, 464446, 464496, 464499, 466466, 466844
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OFFSET
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1,1
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COMMENTS
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Corresponding primes in A107625. Cf. A001744 Every digit contains a loop.
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LINKS
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MATHEMATICA
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Do[id=Union[IntegerDigits[Prime[n]], IntegerDigits[n]]; If[Count[id, 1]+Count[id, 2]+Count[id, 3]+Count[id, 5]+Count[id, 7]==0, Print[n]], {n, 10000}]
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PROG
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(PARI) is_a001744(n) = #setintersect(vecsort(digits(n), , 8), [1, 2, 3, 5, 7])==0
is(n) = is_a001744(n) && is_a001744(prime(n)) \\ Felix Fröhlich, Sep 09 2019
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CROSSREFS
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KEYWORD
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nonn,base,dumb
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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