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A064609
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Partial sums of A034448: sum of unitary divisors from 1 to n.
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3
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1, 4, 8, 13, 19, 31, 39, 48, 58, 76, 88, 108, 122, 146, 170, 187, 205, 235, 255, 285, 317, 353, 377, 413, 439, 481, 509, 549, 579, 651, 683, 716, 764, 818, 866, 916, 954, 1014, 1070, 1124, 1166, 1262, 1306, 1366, 1426, 1498, 1546, 1614, 1664, 1742, 1814, 1884
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Harry J. Smith, Table of n, a(n) for n=1,...,1000
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FORMULA
| a(n) = a(n-1) + A034448(n) = Sum{usigma[j]; j=1..n} where usigma[j] = A034448(j)
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PROG
| (PARI) usigma(n)= { local(f, s=1); f=factor(n); for(i=1, matsize(f)[1], s*=1 + f[i, 1]^f[i, 2]); return(s) } { a=0; for (n=1, 1000, a+=usigma(n); write("b064609.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Sep 20 2009]
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CROSSREFS
| A034448, A064611.
Sequence in context: A198464 A034856 A183865 * A056738 A170907 A143978
Adjacent sequences: A064606 A064607 A064608 * A064610 A064611 A064612
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Sep 24 2001
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