|
Search: id:A073814
|
|
| |
|
| 2, 4, 15, 33, 90, 129, 227, 288, 429, 694, 798, 1149, 1417, 1565, 1879, 2399, 2993, 3201, 3879, 4365, 4623, 5429, 6002, 6920, 8245
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
FORMULA
|
Min{x; c[x]-Max[URS[c[x]]]=p(n)}, p(n)=nth prime. See program.
|
|
EXAMPLE
|
a(6)=129 means that c[129]-Max[URS[c[129]]=Prime[6]: c[129]=169, Max[URS[169]]=Max{26,39,...,143,156}=156; difference=169-156=13=6th prime. Suspicion: A073813(n) is always prime number!
|
|
MATHEMATICA
|
c[x_] := FixedPoint[x+PrimePi[ # ]+1&, x]; tn[x_] := Table[j, {j, 1, x}]; di[x_] := Divisors[x]; rrs[x_] := Flatten[Position[GCD[tn[x], x], 1]]; rs[x_] := Union[rrs[x], di[x]]; urs[x_] := Complement[tn[x], rs[x]]; Do[s=c[n]-Max[urs[c[n]]]; If[s<101&&t[[s]]==0, t[[s]]=n], {n, 1, 10}]; t.
|
|
CROSSREFS
|
Cf. A045763, A073759, A002808, A073813.
Cf. A120389. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 07 2008]
Sequence in context: A019543 A154906 A080623 this_sequence A007122 A005219 A153945
Adjacent sequences: A073811 A073812 A073813 this_sequence A073815 A073816 A073817
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Labos E. (labos(AT)ana.sote.hu), Aug 15 2002
|
|
|
Search completed in 0.002 seconds
|
