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A129913
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a(n) is the number of ways of producing n, with an expression like: +- 1 # 2 # 3 # 4 # 5 # 6 # 7 # 8 # 9, where each # is replaced by any one of +,-,*,/; and the value is computed going left to right.
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1
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694, 299, 143, 171, 156, 156, 183, 155, 167, 434, 160, 140, 129, 111, 89, 147, 114, 201, 171, 94, 87, 90, 68, 95, 130, 130, 44, 120, 41, 72, 76, 72, 50, 81, 50, 53, 137, 49, 46, 78, 41, 75, 36, 61, 28, 123, 35, 86, 47, 40, 40, 47, 40, 37, 109, 61, 32, 58, 23, 53
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OFFSET
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0,1
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LINKS
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EXAMPLE
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Going left-to-right, +1-2/3-4-5*6/7+8*9 = 0; and there are 694 such expressions which yield zero, so a(0)=694.
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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Jason Rodgers (Jason628(AT)gmail.com), Jun 05 2007, Jun 06 2007
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EXTENSIONS
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Corrected and edited by Don Reble, Jun 23 2008
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STATUS
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approved
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