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A082452
a(n)=2n+1 where n is such that A083344(n) is not zero.
3
45, 75, 117, 147, 189, 195, 225, 231, 245, 315, 325, 345, 363, 385, 405, 441, 483, 495, 507, 525, 561, 567, 585, 595, 645, 663, 675, 693, 715, 735, 765, 775, 777, 795, 819, 845, 847, 867, 875, 891, 931, 945, 957, 975, 1001, 1035, 1071, 1083, 1089, 1095, 1125
OFFSET
1,1
EXAMPLE
n=22: 2n+1=45, A057643(45)=5520, a(22)=GCD[45,5520]=15 while A066715[45]=3; a(22)=15-3=12.
MATHEMATICA
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=*)t3=t2-t1; (*A082452=*)1+2*Flatten[Position[Abs[Sign[t3]], 1]];
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Apr 25 2003
STATUS
approved