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A080464
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Product of the two numbers formed by alternate digits of n.
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7
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 0, 6, 12, 18, 24, 30, 36, 42, 48, 54, 0, 7, 14, 21, 28, 35, 42, 49, 56, 63, 0, 8, 16, 24, 32, 40, 48, 56, 64, 72, 0
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OFFSET
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10,3
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LINKS
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FORMULA
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EXAMPLE
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a(132546) = 124 * 356 = 44144.
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MATHEMATICA
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nad[n_]:=Module[{idn=IntegerDigits[n]}, FromDigits[Take[idn, {1, -1, 2}]] FromDigits[ Take[idn, {2, -1, 2}]]]; Array[nad, 120, 10] (* Harvey P. Dale, Aug 07 2019 *)
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PROG
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(PARI) A080464(n, d=digits(n))={n=d*matrix(#d, 2, z, s, if((z-s)%2, 10^((#d-z)\2))); n[1]*n[2]}
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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