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A073722
Least x such that Mod[Sigma[x],Pi[x]]=n or zero if no such number exists.
1
4, 10, 8, 17, 42, 23, 111, 32, 59, 31, 67, 49, 110, 63, 60, 82, 84, 89, 75, 191, 98, 141, 97, 101, 256, 171, 169, 148, 144, 140, 159, 143, 222, 220, 172, 206, 2124, 183, 315, 263, 567, 201, 358, 204, 470, 243, 391, 264, 563, 295, 382, 290, 285, 313, 324, 307
OFFSET
1,1
FORMULA
a(n)=Min{x; Mod[A000203(x)/A000720(x)]=n}
EXAMPLE
n=8: a(8)=32 since Sigma[32]=63,Pi[32]=11, Mod[63,11]=8.
MATHEMATICA
t=Table[0, {100}]; Do[s=Mod[DivisorSigma[1, n], PrimePi[n]]; If[s<101&&t[[s]]==0, t[[s]]=n], {n, 2, 10000}]; t
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Aug 05 2002
STATUS
approved