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%I #10 Nov 21 2019 10:44:12
%S 1,2,5,10,17,37,101,197,257,401,577,677,1297,1601,2917,3137,4357,5477,
%T 7057,8101,8837,12101,13457,14401,15377,15877,16901,17957,21317,22501,
%U 24337,25601,28901,30977,32401,33857,41617,42437,44101,50177
%N Numbers whose divisors have the form m^k + 1, k>1.
%H Jean-François Alcover, <a href="/A054964/b054964.txt">Table of n, a(n) for n = 1..10002</a>
%e 1 =0*0+1, 2 = 1*1+1, 5 = 2*2+1, 10 = 3*3+1 = 2*5, 17 = 4*4+1, ...
%t okQ[n_] := n==1 || n==10 || PrimeQ[n] && IntegerQ[Sqrt[n-1]]; (* _Jean-François Alcover_, Nov 21 2019, after _Charles R Greathouse IV_ *)
%o (PARI) is(n)=(isprime(n) && issquare(n-1)) || n==1 || n==10 \\ _Charles R Greathouse IV_, Mar 11 2014
%Y A002496 together with 1 and 10: a(n+5)=A002496(n+3).
%K nonn,easy,nice
%O 1,2
%A Antreas P. Hatzipolakis (xpolakis(AT)otenet.gr), May 24 2000
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