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 A346018 Triangle read by rows: T(n,k) is the number of integers m such that 1 <= m <= n and gcd(m,n) <= k, 1 <= k <= n. 1
 1, 1, 2, 2, 2, 3, 2, 3, 3, 4, 4, 4, 4, 4, 5, 2, 4, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 7, 4, 6, 6, 7, 7, 7, 7, 8, 6, 6, 8, 8, 8, 8, 8, 8, 9, 4, 8, 8, 8, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 11, 4, 6, 8, 10, 10, 11, 11, 11, 11, 11, 11, 12 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Table of n, a(n) for n=1..78. FORMULA T(n,1) = A000010(n). T(n,2) = A126246(n). T(n,k) = n-1 for A032742(n) <= k <= n-1. T(n,n) = n. EXAMPLE Triangle begins: n\k 1 2 3 4 5 6 7 8 9 10 ---------------------------------- 1: 1 2: 1 2 3: 2 2 3 4: 2 3 3 4 5: 4 4 4 4 5 6: 2 4 5 5 5 6 7: 6 6 6 6 6 6 7 8: 4 6 6 7 7 7 7 8 9: 6 6 8 8 8 8 8 8 9 10: 4 8 8 8 9 9 9 9 9 10 PROG (PARI) T(n, k) = sum(m=1, n, gcd(m, n) <= k); \\ Michel Marcus, Jul 01 2021 CROSSREFS Cf. A000010 (column k=1), A126246 (column k=2), A032742. Sequence in context: A352627 A182210 A078705 * A050331 A259194 A194344 Adjacent sequences: A346015 A346016 A346017 * A346019 A346020 A346021 KEYWORD nonn,tabl AUTHOR Pontus von Brömssen, Jul 01 2021 STATUS approved

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Last modified April 18 10:46 EDT 2024. Contains 371779 sequences. (Running on oeis4.)