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 A079115 Least k such that n+k is squarefree and coprime to n. 2
 1, 1, 2, 1, 1, 1, 3, 3, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 3, 5, 1, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 3, 3, 1, 1, 4, 5, 2, 1, 2, 1, 2, 1, 2, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 1, 3, 3, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 2, 1, 4, 3, 2, 1, 1, 1, 2, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS a(n) = A079114(n) - n. LINKS Antti Karttunen, Table of n, a(n) for n = 1..16384 EXAMPLE From Michael De Vlieger, Nov 23 2017: (Start) First positions of values in a(n):         n   a(n)   --------------         1     1         3     2         7     3        47     4        24     5      1679     6       120     7       843     8      2522     9     72471    10       840    11     64050    13   1674274    15    404580    17   2042040    19 (End) MATHEMATICA Table[Block[{k = 1}, While[Nand[SquareFreeQ[n + k], CoprimeQ[n, n + k]], k++]; k], {n, 105}] (* Michael De Vlieger, Nov 23 2017 *) PROG (PARI) A079115(n) = { my(k=1); while((!issquarefree(n+k))||(gcd(n, n+k)>1), k++); k; } \\ Antti Karttunen, Nov 23 2017 CROSSREFS Cf. A005117, A079114. Sequence in context: A238016 A185812 A152798 * A072906 A239062 A341052 Adjacent sequences:  A079112 A079113 A079114 * A079116 A079117 A079118 KEYWORD nonn AUTHOR Reinhard Zumkeller, Dec 25 2002 STATUS approved

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Last modified July 31 03:23 EDT 2021. Contains 346367 sequences. (Running on oeis4.)