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%I #24 Mar 15 2024 05:40:09
%S 2,7,10,14,16,19,22,23,26,31,36,39,44,45,48,51,52,59,62,65,70,71,74,
%T 79,81,82,83,86,87,90,93,96,99,104,107,110,111,114,118,120,125,128,
%U 131,133,135,138,141,146,149,150,155,156,158,164,169,170,175,178,179
%N Numbers k such that A(k+1) = A(k) + 2, where A() = A005101() are the abundant numbers.
%H Amiram Eldar, <a href="/A303741/b303741.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..5000 from Muniru A Asiru)
%F Sequence is { k | A005101(k+1) = A005101(k) + 2 }.
%p with(numtheory): A:=select(n->sigma(n)>2*n,[$1..1000]): a:=select(j->A[j+1]=A[j]+2,[$1..nops(A)-1]);
%t Position[Differences[Select[Range[750], DivisorSigma[1, #] > 2*# &]], 2] // Flatten (* _Amiram Eldar_, Mar 15 2024 *)
%o (GAP) A:=Filtered([1..1000],n->Sigma(n)>2*n);; a:=Filtered([1..Length(A)-1],i->A[i+1]=A[i]+2);
%Y A231086 is the main entry for this sequence.
%Y Cf. A005101, A096399, A169822.
%K nonn
%O 1,1
%A _Muniru A Asiru_, Jun 22 2018