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A189562 Irregular triangle in which row n has even numbers k that have n solutions to the equation x' = k, where x' denotes the arithmetic derivative (A003415). 3
2, 4, 6, 8, 10, 12, 14, 18, 20, 28, 38, 16, 22, 26, 30, 40, 52, 62, 68, 98, 24, 32, 34, 36, 42, 44, 46, 50, 56, 58, 88, 122, 128, 54, 64, 70, 74, 76, 82, 86, 94, 104, 136, 148, 152, 158, 48, 66, 80, 92, 100, 106, 110, 116, 118, 124, 134, 146, 164, 166, 172, 182 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
The length of row n is A189561(n). The first term in row n is A189558(n).
REFERENCES
See A003415.
LINKS
FORMULA
Row n has even numbers k such that A099302(k) = n.
EXAMPLE
The triangle begins:
2
4, 6, 8
10, 12, 14, 18, 20, 28, 38
16, 22, 26, 30, 40, 52, 62, 68, 98
24, 32, 34, 36, 42, 44, 46, 50, 56, 58, 88, 122, 128
54, 64, 70, 74, 76, 82, 86, 94, 104, 136, 148, 152, 158
48, 66, 80, 92, 100, 106, 110, 116, 118, 124, 134, 146, 164, 166, 172, 182
CROSSREFS
Sequence in context: A321501 A238264 A098807 * A194372 A058218 A264986
KEYWORD
nonn,tabf
AUTHOR
T. D. Noe, Apr 24 2011
STATUS
approved

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Last modified March 28 10:55 EDT 2024. Contains 371241 sequences. (Running on oeis4.)