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 A112790 Array where a(1,1)=1 and m-th term of n-th row is number of terms of (n-1)th row which are coprime to the m-th divisor of n. 1
 1, 1, 1, 2, 2, 2, 0, 0, 3, 1, 2, 2, 1, 1, 4, 4, 2, 0, 0, 0, 4, 1, 1, 3, 2, 3, 2, 4, 4, 2, 0, 2, 0, 0, 0, 6, 2, 2, 0, 2, 0, 4, 2, 2, 2, 4, 0, 0, 0, 0, 5, 1, 2, 2, 2, 2, 2, 2, 6, 6, 2, 0, 0, 2, 0, 0, 6, 2, 2, 2, 4, 0, 4, 0, 4, 2, 2, 0, 2, 0, 0, 0, 0, 0, 8, 2, 2, 3, 0, 3, 0, 4, 0, 0, 0, 4, 0, 0, 1, 0, 0, 6, 2, 2, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Number of terms in row n is A000005(n). LINKS EXAMPLE The irregular array's 5th row is [3,1]. The divisors of 6 are 1, 2, 3 and 6. In the 5th row there are 2 terms coprime to 1, 2 terms coprime to 2, 1 term coprime to 3 and 1 term coprime to 6. So the 6th row of the array is [2,2,1,1]. Array starts 1; 1,1; 2,2; 2,0,0; 3,1; 2,2,1,1; 4,4; 2,0,0,0; CROSSREFS Cf. A000005, A112791. Sequence in context: A262048 A034852 A212438 * A179835 A110857 A108867 Adjacent sequences:  A112787 A112788 A112789 * A112791 A112792 A112793 KEYWORD nonn,tabf AUTHOR Leroy Quet, Dec 31 2005 EXTENSIONS More terms from R. J. Mathar, Aug 29 2007 STATUS approved

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Last modified October 19 02:23 EDT 2018. Contains 316327 sequences. (Running on oeis4.)