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A120804
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Primes with consecutive digits descending.
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5
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OFFSET
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1,1
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COMMENTS
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Digits can be in descending order. After 0 comes 9.
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LINKS
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MATHEMATICA
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f[n_] := Block[{d = Reverse@ Range@n, t = Table[1, {n}]}, Select[ Drop[ Union@ Flatten@ Table[ FromDigits[ Mod[d + i*t, 10]], {i, 10}], 2], PrimeQ@# &]]; Array[f, 1000] // Flatten
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PROG
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(Python)
from sympy import isprime
from itertools import count, islice
def bgen(): yield from (int("".join(str((s0-i)%10) for i in range(d))) for d in count(1) for s0 in range(1, 10))
def agen(): yield from filter(isprime, bgen())
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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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EXTENSIONS
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STATUS
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approved
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