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A088117
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Let the decimal expansion of n be abcd...; then a(n) = {a*bcd... + b*acd... + c*abc... + ...} + {ab*cd} + ... . That is, a(n)=sum over all the digit strings of the product (number obtained by deleting a digit string) * (deleted digit string).
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2
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0, 0, 0, 0, 0, 0, 0, 0, 0, 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
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,12
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COMMENTS
| Each product is used only once.
a(n) = 0 for 0<=n<=9.
The initial 100 terms match those of A007954.
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EXAMPLE
| a(1234) = (234 + 2*134 + 3*124 + 4*123) + (12*34 + 23*14) = 1774.
a(12345) = 2345 + 2*1345 + 3*1245 + 4*1235 + 5*1234 + ( 12*345 + 23*145 + 34*125 + 45*123).
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CROSSREFS
| Cf. A007954, A088116.
Sequence in context: A169931 A141022 A088118 * A171765 A080464 A035930
Adjacent sequences: A088114 A088115 A088116 * A088118 A088119 A088120
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KEYWORD
| base,easy,nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Sep 25 2003
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EXTENSIONS
| Edited by N. J. A. Sloane (njas(AT)research.att.com) at the suggestion of Andrew Plewe, Jul 14 2007
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