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%I #21 Oct 27 2023 22:00:45
%S 24,2160,2640,4320,51840,65280,115200,138240,194400,186048,276480,
%T 483840,622080,700416,950400,984960,1118880,1128960,1612800,2661120,
%U 3937248,3617280,5019840,6128640,5806080,7375680,8467200,11583936
%N Sum of divisors of k such that k and k+1 have the same number and sum of divisors.
%H Amiram Eldar, <a href="/A054005/b054005.txt">Table of n, a(n) for n = 1..1831</a>
%F a(n) = sigma(A054004(n)).
%e See example in A054004.
%t Select[Partition[Table[{n,DivisorSigma[0,n],DivisorSigma[1,n]},{n,116*10^5}],2,1],#[[1,2]]== #[[2,2]] && #[[1,3]]==#[[2,3]]&][[All,1,3]] (* _Harvey P. Dale_, May 16 2023 *)
%Y Cf. A000005, A000203, A002961, A005237, A053249, A054004, A054006, A054007.
%K nonn
%O 1,1
%A _Asher Auel_, Jan 12 2000
%E More terms from _Jud McCranie_, Oct 15 2000
%E Definition clarified by _Harvey P. Dale_, May 16 2023