|
Search: id:A070090
|
|
|
| A070090 |
|
Number of scalene integer triangles with perimeter n and prime side lengths. |
|
+0
6
|
|
| 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 2, 0, 1, 0, 2, 0, 2, 0, 2, 0, 0, 0, 4, 0, 2, 0, 1, 0, 2, 0, 1, 0, 0, 0, 4, 0, 1, 0, 3, 0, 4, 0, 3, 0, 1, 0, 3, 0, 2, 0, 1, 0, 3, 0, 4, 0, 1, 0, 6, 0, 4, 0, 5, 0, 6, 0
(list; graph; listen)
|
|
|
OFFSET
|
1,35
|
|
|
COMMENT
|
a(n) = A070088(n) - A070092(n).
|
|
LINKS
|
R. Zumkeller, Integer-sided triangles
|
|
EXAMPLE
|
For n=15 there are A005044(15)=7 integer triangles: [1,7,7], [2,6,7], [3,5,7], [3,6,6], [4,4,7], [4,5,6] and [5,5,5]: three are scalene: [2<6<7], [3<5<7] and [4<5<6], but only one consists of primes, therefore a(15)=1.
|
|
CROSSREFS
|
Cf. A070080, A070081, A070082, A005044, A070097, A070105, A070114.
Sequence in context: A049767 A091394 A029881 this_sequence A053473 A144764 A084929
Adjacent sequences: A070087 A070088 A070089 this_sequence A070091 A070092 A070093
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 05 2002
|
|
|
Search completed in 0.002 seconds
|
