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A120877
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a(1) = 1. a(n) = number of earlier terms of the sequence that divide the sum of the earlier terms of the sequence.
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2
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1, 1, 2, 3, 2, 3, 6, 7, 2, 4, 2, 4, 2, 4, 2, 4, 3, 12, 12, 12, 12, 12, 13, 2, 2, 5, 10, 23, 2, 3, 15, 2, 7, 18, 12, 12, 14, 32, 16, 31, 2, 6, 6, 9, 20, 13, 7, 13, 2, 2, 6, 6, 7, 17, 6, 6, 8, 2, 6, 3, 16, 19, 9, 32, 16, 33, 9, 45, 10, 3, 19, 5, 16, 20, 20, 35, 4, 8, 2, 3, 17, 19, 17, 19, 22, 35
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OFFSET
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1,3
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COMMENTS
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Sum of first n terms of this sequence is A120878(n).
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LINKS
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EXAMPLE
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The sum of the first 9 terms of the sequence is 27. Among the first 9 terms of the sequence there are 4 terms (a(1)=1, a(2)=1, a(4)=3, a(6)=3) which divide 27.
So a(10) = 4.
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PROG
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(PARI) {m=86; print1(a=1, ", "); v=[a]; for(n=2, m, a=0; q=sum(i=1, n-1, v[i]); for(j=1, n-1, if(q%v[j]==0, a++)); print1(a, ", "); v=concat(v, a))} \\ Klaus Brockhaus, Aug 16 2006
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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