This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A115928 Smallest number which is coprime to the last four predecessors and not occurring earlier; a(1)=1, a(2)=2, a(3)=3 & a(4)=4. 0
 1, 2, 3, 4, 5, 7, 9, 8, 11, 13, 15, 14, 17, 19, 23, 6, 25, 29, 31, 12, 35, 37, 41, 16, 21, 43, 47, 10, 27, 49, 53, 20, 33, 59, 61, 26, 45, 67, 71, 22, 39, 73, 79, 28, 51, 55, 83, 32, 57, 65, 77, 34, 69, 89, 91, 38, 75, 97, 101, 44, 63, 85, 103, 46, 81, 195, 107, 52, 87, 109, 113, 40, 93, 119 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS MATHEMATICA f[s_] := Block[{k = 1, l = Take[s, -4]}, While[ Union[ GCD[k, l]] != {1} || MemberQ[s, k], k++]; Append[s, k]]; Nest[f, {1, 2, 3, 4}, 70] CROSSREFS Cf. A084937, A103683. Sequence in context: A161751 A245820 A105362 * A247665 A117331 A080612 Adjacent sequences:  A115925 A115926 A115927 * A115929 A115930 A115931 KEYWORD easy,nonn AUTHOR Robert G. Wilson v, Jun 26 2011 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 14 22:42 EST 2019. Contains 329987 sequences. (Running on oeis4.)