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 A340275 Number of partitions of n into 3 parts whose smallest two parts are relatively prime. 2
 0, 0, 1, 1, 2, 2, 3, 4, 5, 5, 7, 8, 10, 11, 12, 13, 16, 17, 20, 22, 24, 25, 29, 30, 33, 35, 38, 40, 45, 47, 52, 55, 58, 60, 64, 66, 72, 75, 79, 81, 88, 90, 97, 101, 105, 108, 116, 119, 126, 130, 135, 139, 148, 151, 157, 161, 167, 171, 181, 183, 193, 198, 204, 209, 217, 221 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 LINKS Table of n, a(n) for n=1..66. Index entries for sequences related to partitions FORMULA a(n) = Sum_{k=1..floor(n/3)} Sum_{i=k..floor((n-k)/2)} floor(1/gcd(i,k)). MATHEMATICA Table[Sum[Sum[Floor[1/GCD[i, k]], {i, k, Floor[(n - k)/2]}], {k, Floor[n/3]}], {n, 100}] CROSSREFS Cf. A023023, A340276, A340278. Sequence in context: A342519 A307780 A340276 * A348323 A367214 A342499 Adjacent sequences: A340272 A340273 A340274 * A340276 A340277 A340278 KEYWORD nonn AUTHOR Wesley Ivan Hurt, Jan 02 2021 STATUS approved

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Last modified August 6 15:42 EDT 2024. Contains 374974 sequences. (Running on oeis4.)