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A093993
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Number of divisors of n with a prime digital sum.
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0
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0, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 3, 0, 3, 2, 2, 0, 2, 0, 3, 3, 2, 1, 3, 2, 1, 1, 3, 1, 4, 0, 3, 2, 2, 2, 3, 0, 2, 1, 3, 1, 5, 1, 2, 2, 2, 1, 4, 2, 4, 1, 2, 0, 2, 2, 4, 1, 3, 0, 6, 1, 1, 3, 3, 2, 3, 1, 2, 2, 5, 0, 3, 0, 2, 3, 3, 2, 2, 0, 4, 1, 2, 1, 6, 2, 2, 2, 2, 1, 4, 1, 3, 1, 3, 1, 5, 0, 5, 2, 5, 1, 4, 0, 3, 4
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OFFSET
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1,6
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LINKS
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EXAMPLE
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a(12)=3 because the divisors of 12 are: [1, 2, 3, 4, 6, 12] and 2, 3 and 1+2=3 are primes.
a(98)=5 because the divisors of 98 are: [1, 2, 7, 14, 49, 98] and 2, 7, 1+4=5, 4+9=13 and 9+8=17 are primes.
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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STATUS
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approved
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