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%I #25 Oct 27 2023 22:00:45
%S 206,957,1364,2974,4364,14841,18873,19358,20145,24957,36566,56564,
%T 74918,79826,79833,92685,111506,116937,138237,147454,161001,162602,
%U 174717,190773,193893,201597,230390,274533,347738,416577,422073,430137
%N Numbers k such that k and k+1 have the same sum but an unequal number of divisors.
%H Amiram Eldar, <a href="/A054007/b054007.txt">Table of n, a(n) for n = 1..8304</a> (terms below 10^13, calculated from the b-file at A002961)
%F Members of A002961 which are not members of A054004
%e The divisors of 206 are 1, 2, 103, 206, so tau(206) = 4 and sigma(206) = 312; the divisors of 207 are 1, 3, 9, 23, 69, 207, so tau(207) = 6 and sigma(207) = 312. Hence, the integer 206 belongs to this sequence. - _Bernard Schott_, Oct 18 2019
%t Select[Range[100000], DivisorSigma[0, #] != DivisorSigma[0, # + 1] && DivisorSigma[1, #] == DivisorSigma[1, # + 1] &] (* _Jayanta Basu_, Mar 20 2013 *)
%Y Cf. A000005, A000203, A002961, A005237, A053249, A054004, A054005, A054006.
%K nonn
%O 1,1
%A _Asher Auel_, Jan 12 2000
%E More terms from _Jud McCranie_, Oct 15 2000