|
%I #12 Nov 27 2019 05:29:38
%S 9,21,33,49,57,69,77,81,93,105,121,129,133,141,161,165,177,189,201,
%T 209,213,217,237,245,249,253,285,297,301,309,321,329,341,345,361,381,
%U 385,393,413,417,437,441,453,465,469,473,489,497,501,513,517,525,529,537,553,573
%N Numbers of the form 4k+1 with greatest prime divisor of the form 4m-1.
%C All terms of A107978 are in the sequence.
%H Amiram Eldar, <a href="/A176258/b176258.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[4 Range@ 150 + 1, Mod[#, 4] == 3 &[FactorInteger[#][[-1, 1]]] &] (* _Michael De Vlieger_, Feb 07 2016 *)
%o (PARI) isok(n) = (n != 1) && ((n % 4) == 1) && ((vecmax(factor(n)[,1]) % 4) == 3); \\ _Michel Marcus_, Feb 07 2016
%Y Cf. A176257, A176256, A176255, A107978, A002148, A002145, A016813, A004767.
%K nonn
%O 1,1
%A _Vladimir Shevelev_, Apr 13 2010
%E Corrected and extended by _Michel Marcus_, Feb 07 2016
|
