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 A175307 a(n) = the number of terms in row n of A175306. 2
 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 4, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(2n) = 1, and a(3n)=1, for all positive integers n. LINKS Robert Israel, Table of n, a(n) for n = 1..10000 MAPLE A175307:=proc(n) local R, last, k, P; R:= n; last:= n; P:= n; while igcd(last, 6)=1 do   for k from last+1 do     if igcd(k-1, P) = 1 and igcd(k, P) = 1 and igcd(k+1, P) =1 then       R:= R, k; last:= k; P:= P*k; break     fi   od od; nops([R]) end proc: map(A175307, [\$1..100]); # Robert Israel, Feb 10 2017 CROSSREFS Cf. A175306 Sequence in context: A276949 A205794 A241665 * A316557 A032436 A280274 Adjacent sequences:  A175304 A175305 A175306 * A175308 A175309 A175310 KEYWORD nonn AUTHOR Leroy Quet, Mar 26 2010 STATUS approved

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Last modified December 11 04:29 EST 2018. Contains 318049 sequences. (Running on oeis4.)