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%I A145047 #5 Jan 12 2020 23:45:49
%S A145047 1237,1621,1721,1933,1949,1993,2221,2237,2309,2341,2473,2621,2657,
%T A145047 2789,2797,2857,2953,3221,3361,3533,3677,3881,3889,3917,4133,4457,
%U A145047 4481,4549,4813,4889,4973,5153,5189,5261,5441,5653,5717,5813,6101,6217,6301,6329
%N A145047 Primes p of the form 4k+1 for which s=10 is the least positive integer such that sp-(floor(sqrt(sp)))^2 is a square.
%C A145047 Conjecture: The least positive integer s can take values only from A008784 (see for s=1,2,5,10 sequences A145016, A145022, A145023 and this sequence).
%e A145047 a(1)=1237 since p=1237 is the least prime of the form 4k+1 for which sp-(floor(sqrt(sp)))^2 is not a square for s=1..9, but 10p-(floor(sqrt(10p)))^2 is a square (for p=1237 it is 49).
%Y A145047 Cf. A145016, A145017, A145022, A145023, A008784.
%K A145047 nonn
%O A145047 1,1
%A A145047 _Vladimir Shevelev_, Sep 30 2008, Oct 05 2008

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