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A325312 Odd numbers n for which sigma(n^2) == 3 (mod 4) and sigma(n^2) > 2*n^2. 3
105, 315, 495, 735, 945, 1155, 1485, 1995, 2205, 2415, 2625, 2835, 2925, 3135, 3255, 3315, 3465, 3795, 4455, 4515, 4935, 5115, 5145, 5445, 5655, 5985, 6195, 6615, 6825, 7035, 7095, 7245, 7455, 7605, 7755, 7875, 8085, 8295, 8505, 8715, 8775, 8925, 9009, 9405, 9735, 9765, 9945, 10395, 10725, 10815, 11235, 11385, 11781, 12375 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Square roots of A325311, odd abundant numbers n for which sigma(n) == 3 mod 4.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

Index entries for sequences related to sigma(n)

FORMULA

a(n) = A000196(A325311(n)).

PROG

(PARI) isA325312(n) = { my(t=sigma(n*n)); (n%2 && 3==(t%4) && t>(2*n*n)); };

CROSSREFS

Cf. A000196, A325311.

Intersection of A174830 and A324909.

Sequence in context: A010090 A306122 A174830 * A147576 A145752 A195266

Adjacent sequences:  A325309 A325310 A325311 * A325313 A325314 A325315

KEYWORD

nonn

AUTHOR

Antti Karttunen, Apr 20 2019

STATUS

approved

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Last modified January 28 10:02 EST 2020. Contains 331319 sequences. (Running on oeis4.)