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A096301
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Product of nonzero digits(sum of digits(n^n)).
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1
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1, 4, 9, 3, 1, 14, 10, 21, 20, 1, 4, 20, 40, 10, 81, 64, 72, 8, 14, 3, 7, 32, 24, 15, 5, 20, 72, 18, 42, 18, 32, 10, 14, 8, 12, 14, 14, 60, 18, 2, 24, 15, 9, 30, 18, 30, 84, 27, 75, 5, 16, 8, 15, 168, 32, 27, 20, 56, 28, 24, 128, 20, 180, 224, 70, 15, 60, 120, 196, 90, 144, 200, 24
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OFFSET
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1,2
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COMMENTS
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Conjecture: a(n) = a(n+1) for infinitely many positive integers. Largest found is n=4462, i.e. pnd(sd(4462^4462)) = pnd(sd(4463^4463)) = 126.
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LINKS
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MATHEMATICA
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Array[Times@@Select[IntegerDigits[Total[IntegerDigits[#^#]]], #>0&]&, 80] (* Harvey P. Dale, Sep 30 2012 *)
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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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