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 A090788 Numbers that can be expressed as the difference of the squares of primes in just two distinct ways. 24
 72, 360, 432, 528, 768, 888, 960, 1032, 1080, 1128, 1272, 1392, 1488, 1512, 1608, 1632, 1728, 1920, 2088, 2112, 2232, 2352, 2400, 2448, 2568, 2688, 2808, 3048, 3168, 3240, 3288, 3480, 3648, 3768, 4008, 4032, 4128, 4248, 4272, 4392, 4488, 4512, 4992 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 72 = 11^2 - 7^2 = 19^2 - 17^2. PROG (PARI) i=4; while(i<=5000, k=0; m=2; while(m*m<=i, if(i%(2*m)==0, a=(i/m-m)/2; b=a+m; if(isprime(a)&&isprime(b), k+=1)); m+=2); if(k==2, print1(i, ", ")); i+=4) \\ Antonio Roldán, Nov 06 2018 CROSSREFS Cf. A078667, A090781, A090782. Sequence in context: A157909 A107314 A223472 * A334902 A192792 A303621 Adjacent sequences:  A090785 A090786 A090787 * A090789 A090790 A090791 KEYWORD nonn AUTHOR Ray Chandler, Feb 14 2004 STATUS approved

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Last modified August 4 00:54 EDT 2020. Contains 336201 sequences. (Running on oeis4.)