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proposed
approved
editing
proposed
0, 1, 3, 4, 10, 9, 21, 16, 27, 25, 55, 36, 78, 49, 45, 64, 136, 81, 171, 100, 84, 121, 253, 144, 250, 169, 243, 196, 406, 105, 465, 256, 198, 289, 175, 324, 666, 361, 273, 400, 820, 189, 903, 484, 405, 529, 1081, 576, 1029, 625, 459, 676
2,2
1,3
(PARI) as(n) = my(f=factor(n)); vecsum(Vec(select(x->(x==1), vector(n-1, j, sum(k=1, #f~, gcd(j, f[k, 1]) == 1)), 1))); \\ Michel Marcus, Oct 25 2017
a(1)=0 prepended by Michel Marcus, Oct 25 2017
approved
editing
Leroy Quet , Mar 04 2007
_Leroy Quet _ Mar 04 2007
More terms from _R. J. Mathar (mathar(AT)strw.leidenuniv.nl), _, Oct 08 2007
Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> (listed in lieu of email address)
nonn,new
nonn
Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> (listed in lieu of email address)
nonn,new
nonn
Leroy Quet (qq-quet(AT)mindspring.com), Mar 04 2007
a(n) = sum of terms in nth n-th row of irregular table A128487.
0, 1, 3, 4, 10, 9, 21, 16, 27, 25, 55, 36, 78, 49, 45, 64, 136, 81, 171, 100, 84, 121, 253, 144, 250, 169, 243, 196, 406, 105, 465, 256, 198, 289, 175, 324, 666, 361, 273, 400, 820, 189, 903, 484, 405, 529, 1081, 576, 1029, 625, 459, 676
1,3
2,2
more,nonn,new
nonn
More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 08 2007