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 A070138 Number of integer triangles with an integer area having relatively prime sides a, b and c such that a + b + c = n. 17
 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 2, 0, 0, 0, 1, 0, 2, 0, 1, 0, 0, 0, 1, 0, 2, 0, 0, 0, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0, 3, 0, 1, 0, 1, 0, 2, 0, 1, 0, 0, 0, 1, 0, 1, 0, 2, 0, 0, 0, 5, 0, 0, 0, 0, 0, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,36 COMMENTS From Peter Kagey, Jan 30 2018: (Start) a(k) > 0 if and only if k is in A096468. Records appear at indices 12, 36, 54, 84, 98, 162, 242, 338, 484, 578, .... a(2k - 1) = 0 for all integers k > 0. (End) LINKS Peter Kagey, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Heronian Triangle. R. Zumkeller, Integer-sided triangles CROSSREFS Cf. A051493, A051516, A070088, A070109, A070143, A096468, A239246. Sequence in context: A208575 A070203 A070201 * A024153 A341523 A079127 Adjacent sequences:  A070135 A070136 A070137 * A070139 A070140 A070141 KEYWORD nonn AUTHOR Reinhard Zumkeller, May 05 2002 EXTENSIONS Corrected by T. D. Noe, Jun 17 2004 STATUS approved

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Last modified April 14 12:04 EDT 2021. Contains 342949 sequences. (Running on oeis4.)