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Search: id:A083344
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| 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 14, 0, 0, 30, 0, 0, 0, 0, 0, 0, 4, 0, 0
(list; graph; listen)
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OFFSET
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1,22
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FORMULA
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a(n)=GCD[2n+1, LCM[1+D(2n+1)]]-GCD[2n+1, sigma(2n+1)], GCD[2n+1, A057643(2n+1)]-GCD[2n+1, A000203(2n+1)], where D(x)=divisor-set of x
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EXAMPLE
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n=22: 2n+1=45, A057643(45)=5520, a(22)=GCD[45,5520]=15 while A066715[45]=3; a(22)=15-3=12; sites where nonzero terms appear see in A082452.
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MATHEMATICA
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di[x_] := Apply[LCM, Divisors[x]+1] (*A066715=*)t1=Table[GCD[2*n+1, DivisorSigma[1, 2*n+1]], {n, 1, 2048}]; (*A082457=*)t2=Table[GCD[2*w+1, di[1+2*w]], {w, 1, 2048}]; (*A083344=*)t2-t1;
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CROSSREFS
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Cf. A057643, A066715, A000203, A082457, A082452.
Adjacent sequences: A083341 A083342 A083343 this_sequence A083345 A083346 A083347
Sequence in context: A046844 A066953 A004022 this_sequence A063863 A101364 A104203
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KEYWORD
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sign
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Apr 25 2003
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