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A065132
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Arithmetic mean of first n terms of A008472 is an integer.
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1
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2, 13, 134, 167, 2239, 62268, 75255, 135681, 439867, 18139940, 23671044, 40892256, 312083956, 724031017, 1990127567, 2144843867, 2588619526, 7439533243, 15054156002, 54892225873, 69959798320, 79760490898, 282311798922
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| Integers n that divide A024924(n)=A008472(1)+A008472(2)+...+A008472(n).
Also, integers n that divide A024934(n).
Prime terms are listed in A143851.
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EXAMPLE
| Sum of first 13 terms of A008472 gives A024924(13) = 65 which is divisible with n = 13, so 13 is here: 0+2+3+2+5+5+7+2+3+7+11+5+13 = 65 = 13*5 = A024924(13)
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MATHEMATICA
| s=0; Do[s=s+sp[n]; If[IntegerQ[n/25000], Print[n]]; If[IntegerQ[s/n], Print[{n, s, s/n}]], {n, 2, 4000000}] where sp[n]=A008472(n).
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CROSSREFS
| Cf. A024924, A008472.
Sequence in context: A085882 A041509 A079165 * A047856 A187021 A152059
Adjacent sequences: A065129 A065130 A065131 * A065133 A065134 A065135
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KEYWORD
| nonn,changed
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Oct 15 2001
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EXTENSIONS
| a(10)-a(19) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Nov 22 2009
a(20)-a(23) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Aug 31 2010
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