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A274116 (1+e)-sigma amicable numbers. 2

%I #17 Jun 17 2016 02:15:39

%S 220,284,366,378,2620,2924,3864,4584,5020,5564,16104,16536,16632,

%T 16728,26448,28752,29760,30912,43524,53692,63020,67344,69552,69615,

%U 76084,87633,100485,122265,124155,139815,142290,142310,168730,179118,196248,196724,198990,202444

%N (1+e)-sigma amicable numbers.

%C The first time a pair ordered by its first element is not adjacent is x = 16104, y = 16632 which correspond to a(11) and a(13), respectively.

%H Paolo P. Lava, <a href="/A274116/b274116.txt">Table of n, a(n) for n = 1..500</a>

%e (1+e)-sigma(366) = 378 and (1+e)-sigma(378) = 366.

%p with(numtheory): T:=proc(n) local a,d,p,e,s,sp; a:=1;

%p for d in ifactors(n)[2] do p:=op(1,d); e:= op(2,d); sp:=1;

%p for s in divisors(e) do sp:=sp+p^s; od: a:=a*sp; od: a; end:

%p P:=proc(q) local n,x,y; for n from 1 to q do x:=T(n)-n; y:=T(x)-x;

%p if n=y and x<>y then print(n); fi; od; end: P(10^10);

%Y Cf. A049603, A051378, A274118.

%K nonn,easy

%O 1,1

%A _Paolo P. Lava_, Jun 10 2016

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Last modified May 9 05:10 EDT 2024. Contains 372344 sequences. (Running on oeis4.)