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Search: id:A061150
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| A061150 |
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a(n)=Sum_{d|n} d*ithprime(d). |
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+0
4
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| 2, 8, 17, 36, 57, 101, 121, 188, 224, 353, 343, 573, 535, 729, 777, 1036, 1005, 1406, 1275, 1801, 1669, 2087, 1911, 2861, 2482, 3167, 3005, 3753, 3163, 4541, 3939, 5228, 4879, 5737, 5391, 7314, 5811, 7475, 7063, 8873, 7341, 9957, 8215, 10607, 9849
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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Equals M * V, where M = A127093 as an infinite lower triangular matrix and V = A000040, the sequence of primes as a vector. E.g. a(4) = 36 = 1*2 + 2*3 + 4*7, where (1, 2, 0, 4) = row 4 of A127093 and 2, 3 and 7 are p(1), p(2), p(4). - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jan 11 2007
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EXAMPLE
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a(4)=36 because the divisors of 4 are 1,2,4 and 1*p(1)+2*p(2)+4*p(4)=1*2+2*3+4*7=36.
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MAPLE
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with(numtheory): a:=proc(n) local div: div:=divisors(n): sum(div[j]*ithprime(div[j]), j=1..tau(n)) end: seq(a(n), n=1..55); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Jan 20 2007
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CROSSREFS
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Cf. A007441, A007445, A030009, A061151-A061152.
Cf. A127093.
Sequence in context: A131362 A066564 A034972 this_sequence A160189 A154349 A073601
Adjacent sequences: A061147 A061148 A061149 this_sequence A061151 A061152 A061153
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KEYWORD
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easy,nonn
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AUTHOR
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Vladeta Jovovic (vladeta(AT)eunet.rs), Apr 16 2001
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EXTENSIONS
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Edited by N. J. A. Sloane (njas(AT)research.att.com), May 04 2007
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