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A326183
Numbers n for which A003961(n) <= A064989(sigma(A003961(n))), but which are not squares.
2
97560000, 140040000, 161640000, 188280000, 392760000, 414360000, 429480000, 432360000, 443160000, 474840000, 494280000, 522360000, 582840000, 589320000, 673560000, 715320000, 767160000, 842040000, 888120000, 903960000, 918360000, 932760000, 1026360000, 1047240000
OFFSET
1,1
COMMENTS
At least for 1 <= n <= 24 it holds that A052126(a(n)) is square, and moreover, apart from a(20), that square is 360000, while A052126(a(20)) = A052126(903960000) = 29160000.
The largest prime factors (that are also unitary in case of 24 initial terms) are A006530(a(n)): 271, 389, 449, 523, 1091, 1151, 1193, 1201, 1231, 1319, 1373, 1451, 1619, 1637, 1871, 1987, 2131, 2339, 2467, 31, 2551, 2591, 2851, 2909.
CROSSREFS
Setwise difference A326182 \ A000290.
Sequence in context: A250964 A075010 A214559 * A184151 A096710 A322682
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 17 2019
STATUS
approved