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%I #5 Mar 31 2023 07:01:26
%S 2457405145194,2601523139214,3320774552094,3490250769005,
%T 3733421997305,3934651766045,3954730124345,4514767592334,
%U 4553585751714,4563327473705,5226433847634
%N Numbers k such that k and k+1 are both primitive unitary abundant numbers (definition 2, A302574).
%C There are no more terms below 10^13.
%C There are no numbers k such that k and k+1 are both unitary abundant numbers with definition 1 (A302573) below 10^13.
%t f1[p_, e_] := 1 + 1/p^e; f2[p_, e_] := p^e/(p^e + 1);
%t puabQ[n_] := (r = Times @@ f1 @@@ (f = FactorInteger[n])) > 2 && r * Max @@ f2 @@@ f <= 2;
%t Select[Import["https://oeis.org/A331412/b331412.txt", "Table"][[;; , 2]], puabQ[#] && puabQ[# + 1] &]
%Y Subsequence of A034683, A302574 and A331412.
%Y Cf. A302573.
%Y Similar sequences: A283418, A330872.
%K nonn,more
%O 1,1
%A _Amiram Eldar_, Mar 31 2023
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