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Search: id:A108298
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| A108298 |
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Sum of the first 10^n terms in A097975. a(n) = sum_{m=1..10^n} t(m), where t(m) is the sum of the prime divisors of m that are greater than or equal to sqrt(m). |
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+0
1
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| 0, 30, 1767, 131149, 9901470, 780654405, 64077091471, 5427484448862
(list; graph; listen)
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OFFSET
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0,2
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COMMENT
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Does a(n+1)/a(n) converge?
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EXAMPLE
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The first 10^2 terms in A097975 sum to 1767, so a(2) = 1767.
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MATHEMATICA
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s = 0; k = 1; Do[l = Select[Select[Divisors[n], PrimeQ], # >= Sqrt[n]&]; If[Length[l] > 0, s += l[[1]]]; If[n == k, Print[s]; s = 0; k *= 10], {n, 1, 10^7}]
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CROSSREFS
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Cf. A097975.
Sequence in context: A103917 A089550 A007804 this_sequence A042743 A042740 A112003
Adjacent sequences: A108295 A108296 A108297 this_sequence A108299 A108300 A108301
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KEYWORD
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more,nonn
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AUTHOR
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Ryan Propper (rpropper(AT)stanford.edu), Jul 24 2005
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