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_Cino Hilliard (hillcino368(AT)hotmail.com), _, Mar 01 2009
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Better definition and Mma program from Zak Seidov, Mar 14 2013
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The differences between the primes and the next squares are a(n) = least prime p such that p + prime(n) is a square.
It is appropriate to add a counter to the program to ensure a square is found for all primes <= n. Here we set n^2 as the difference upper bound. This appears to be high but with no loss in efficiency since we break out of the loop when the first square is found. This partial listing was generated for primes < 1000. Notice that 1601 would have been missed had we set the difference upper bound to 1000.
Or, least prime p such that p + prime(n) is a square. - Zak Seidov, Mar 14 2013~
Better definition from Zak Seidov, Mar 14 2013
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Or, least prime p such that p + prime(n) is a square. - Zak Seidov, Mar 14 2013~
Zak Seidov, <a href="/A157480/b157480.txt">Table of n, a(n) for n = 1..10000</a>
Table[p=Prime[n]; b=Ceiling[Sqrt[p]]; While[!PrimeQ[x=b^2-p], b++]; x, {n, 72}]
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