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A070971
a(n) is the smallest positive integer m for which A070194(m) (i.e., the maximal gap in {k|gcd(k,m) = 1, 1 <= k <= m-1}) is n.
4
3, 4, 15, 6, 105, 30, 1155, 770, 36465, 210, 15015, 6006, 255255, 2310, 8580495, 102102, 4849845, 72930, 20056049013, 74364290, 5898837945, 30030, 3234846615, 881790, 195282582495, 510510, 218257003965, 20281170, 100280245065, 17160990, 934482952262145, 6614136163635
OFFSET
1,1
COMMENTS
a(n) is the least x such that maximal gap in RRS of x equals n: a(n) = max{x: A070194(x) = n}
For n > 2, same as A128759, which gives the least k such that the Jacobsthal function A048669(k) equals n. See A128759 for more comments. - T. D. Noe, Mar 28 2007
EXAMPLE
A070194 begins with 1,2,1,4,... with offset 3, so a(4)=6.
MATHEMATICA
gw[x_] := Table[GCD[w, x], {w, 1, x}] rrs[x_] := Flatten[Position[gw[x], 1]] dr[x_] := Delete[RotateLeft[rrs[x]]-rrs[x], -1] t=Table[0, {25}]; Do[s=Max[dr[n]]; If[s<26&&t[[s]]==0, t[[s]]=n], {n, 3, 10000}]; t (* Labos Elemer, Oct 09 2002 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
John W. Layman, May 17 2002
EXTENSIONS
a(13)-a(18) from T. D. Noe, Mar 28 2007
a(19) onwards from Don Reble, Oct 17 2013
STATUS
approved