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%I #10 Nov 17 2022 14:12:24
%S 104,134,164,314,404,494,524,554,566,584,674,692,734,764,854,944,974,
%T 1124,1154,1196,1214,1304,1322,1364,1394,1484,1574,1682,1724,1754,
%U 1784,1814,1826,1844,1994,2024,2144,2204,2384,2414,2456,2474,2564,2624,2654,2804,2834,3002
%N Even numbers k such that sigma(k) + sigma(k+2) < 2*sigma(k+1); even terms in A053229.
%C Even numbers k such that A053223(k) < 0.
%H Jianing Song, <a href="/A358396/b358396.txt">Table of n, a(n) for n = 1..20000</a>
%e 104 is a term since sigma(105) = 192 is greater than the average of sigma(104) = 210 and sigma(106) = 162.
%o (PARI) isA358396(n) = !(n%2) && (sigma(n) + sigma(n+2) < 2*sigma(n+1))
%Y Cf. A053229, A053223, A000203 (sigma), A358395.
%K nonn
%O 1,1
%A _Jianing Song_, Nov 13 2022