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%I #10 Oct 27 2023 22:00:45
%S 1,4,2,6,14,13,19,10,12,29,2,26,40,15,6,53,4,48,52,6,6,24,67,21,44,48,
%T 40,30,106,43,76,30,72,121,44,88,65,42,116,12,90,122,40,24,154,15,115,
%U 112,18,30,54,170,64,134,96,28,2,36,227,18,68,184,79,120,176,132,148
%N First differences of sigma(n) that are negative.
%H Harvey P. Dale, <a href="/A053227/b053227.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A053222(A053226(n))
%p with(numtheory): seq( `if`((sigma(i) > sigma(i+1)),(sigma(i) - sigma(i+1)),print( )), i=1..200);
%t Abs[Select[Differences[DivisorSigma[1,Range[200]]],#<0&]] (* _Harvey P. Dale_, Apr 17 2022 *)
%Y Cf. A000203, A053222, A053225.
%K nonn
%O 1,2
%A _Asher Auel_, Jan 06 2000
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