This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A152757 #10 Jan 06 2019 05:45:04 %S A152757 2,3,4,5,6,7,9,10,11,13,14,16,17,18,19,20,21,22,23,26,27,28,29,31,34, %T A152757 37,38,41,43,45,46,47,49,52,53,55,57,58,59,61,62,64,67,70,71,73,74,75, %U A152757 76,77,79,82,83,86,88,89,91,93,94,95,97,99,101,103,104,106,107,109,110,111 %N A152757 Numbers k such that the deficiency of k plus the number of proper divisors of k is a prime number (see A152864). %H A152757 B. D. Swan, <a href="/A152757/b152757.txt">Table of n, a(n) for n = 1..50000</a> %p A152757 with(numtheory): a := proc (n) if isprime(2*n-sigma(n)+tau(n)-1) = true then n else end if end proc: seq(a(n), n = 1 .. 120); # _Emeric Deutsch_, Jan 08 2009 %Y A152757 Cf. A000005, A000203, A033879, A032741, A152770, A152864. %K A152757 nonn %O A152757 1,1 %A A152757 _Omar E. Pol_, Dec 14 2008 %E A152757 Extended by _Emeric Deutsch_, Jan 08 2009 %E A152757 Name edited by _Jon E. Schoenfield_, Jan 06 2019