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 A077128 Smallest number greater than the previous term which is relatively prime to each of the group of the next n numbers. 2
 2, 5, 7, 11, 17, 23, 29, 37, 47, 59, 67, 79, 97, 107, 127, 137, 157, 173, 191, 211, 233, 257, 277, 307, 331, 353, 379, 409, 439, 467, 499, 541, 563, 599, 631, 673, 709, 743, 787, 821, 863, 907, 947, 991, 1039, 1087, 1129, 1181, 1229, 1277, 1327, 1381, 1433 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Conjecture : every member is a prime. LINKS EXAMPLE a(6) = 23 is the smallest number coprime to 16,17,18,19,20 and 21. - R. J. Mathar, Sep 02 2008 MAPLE A000217 := proc(n) n*(n+1)/2 ; end: A077128 := proc(n) option remember ; local ts, a, goodk, k ; if n = 1 then RETURN(2) ; fi; ts := [seq(A000217(n-1)+i, i=1..n)] ; for a from procname(n-1)+1 do goodk := true ; for k in ts do if gcd(a, k) <> 1 then goodk := false; break ; fi; od: if goodk then RETURN(a) ; fi; od: end: for n from 1 to 100 do printf("%d, ", A077128(n)) ; od: # R. J. Mathar, Sep 02 2008 CROSSREFS Cf. A097050. - R. J. Mathar, Sep 02 2008 Sequence in context: A142352 A290012 A062044 * A106008 A138244 A326505 Adjacent sequences:  A077125 A077126 A077127 * A077129 A077130 A077131 KEYWORD nonn AUTHOR Amarnath Murthy, Oct 29 2002 EXTENSIONS Extended beyond a(10) by R. J. Mathar, Sep 02 2008 STATUS approved

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Last modified April 5 18:26 EDT 2020. Contains 333246 sequences. (Running on oeis4.)