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A276162 Square array read by antidiagonals: T(n,k) = Product_{i = 1..k} gcd(n, i).

%I A276162 #22 Aug 01 2019 04:09:12
%S A276162 1,1,1,1,2,1,1,1,2,1,1,2,3,4,1,1,1,2,3,4,1,1,2,1,8,3,8,1,1,1,6,1,8,9,
%T A276162 8,1,1,2,1,12,5,16,9,16,1,1,1,2,1,12,5,16,9,16,1,1,2,3,8,1,72,5,64,27,
%U A276162 32,1,1,1,2,3,8,1,72,5,64,27,32,1,1,2,1,4
%N A276162 Square array read by antidiagonals: T(n,k) = Product_{i = 1..k} gcd(n, i).
%H A276162 Peter Kagey, <a href="/A276162/b276162.txt">Table of n, a(n) for n = 1..10000</a>
%H A276162 Mohamed Abobakr, <a href="http://math.stackexchange.com/questions/1897045/greatest-common-divisor-sequence/1897046">Greatest common divisor sequence</a>
%e A276162 T(6, 3) = gcd(6, 1) * gcd(6, 2) * gcd(6, 3) = 6.
%o A276162 (PARI) T(n,k)=prod(i=2,k,gcd(n,i))
%o A276162 for(s=1,15,for(k=1,s-1, print1(T(s-k,k)", "))) \\ _Charles R Greathouse IV_, Aug 22 2016
%o A276162 (Haskell) a276162T n k = product $ map (gcd n) [1..k]
%o A276162 -- _Peter Kagey_, Aug 23 2016
%Y A276162 Cf. A051190, A067911, A092287.
%K A276162 nonn,tabl
%O A276162 1,5
%A A276162 _Peter Kagey_, Aug 22 2016