cp's OEIS Frontend

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.

A106575 Perfect squares which are both the sum and the difference of two primes.

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%I A106575 #18 Sep 08 2022 08:45:18
%S A106575 4,9,16,36,64,81,100,144,196,225,256,324,400,441,484,576,676,784,900,
%T A106575 1024,1089,1156,1296,1444,1600,1764,1936,2116,2304,2500,2704,2916,
%U A106575 3136,3364,3600,3844,4096,4356,4624,4900,5184,5476,5776,6084,6400,6724,7056
%N A106575 Perfect squares which are both the sum and the difference of two primes.
%C A106575 Equals A106548 with 0's removed.
%C A106575 Appears to contain all even squares.
%C A106575 By well-known conjectures, every even integer > 2 is both the sum and the difference of two primes; this would be a special case. - _Franklin T. Adams-Watters_, Sep 13 2015
%e A106575 2^2 = 4 is in the sequence because it is the sum of two primes (2+2) and the difference of two primes (7-3). 10^2 = 100 is in the sequence because it is the sum and the difference of two primes: 97+3 (or 89+11) and 103-3. 11^2 = 121 is not in the sequence because it is neither the sum nor the difference of two primes. 13^2 = 169 is the sum of two primes (167+2), but it doesn't figure here since it is not the difference of two primes.
%o A106575 (Magma) [ s: n in [1..85] | exists(t){ k: k in [1..s] | s-k gt 0 and IsPrime(k) and IsPrime(s-k) } and exists(u){ k: k in [1..s] | IsPrime(k) and IsPrime(s+k) } where s is n^2 ]; /* _Klaus Brockhaus_, Nov 17 2010 */
%Y A106575 Cf. A106544-A106548, A106562-A106564, A106571, A106573, A106574, A106577.
%K A106575 easy,nonn
%O A106575 1,1
%A A106575 _Alexandre Wajnberg_, May 09 2005
%E A106575 Extended by _Ray Chandler_, May 12 2005
%E A106575 Edited by _Klaus Brockhaus_, Nov 17 2010