A091719 - OEIS

%I #13 Nov 22 2023 17:39:05

%S 1,1,1,1,1,1,1,1,2,6,14,7,1,1,1,11,33,11,35,1,33,6,1,5,1,2,14,2,11,1,

%T 2,11,69,1,1,1,1,11,55,21,21,11,11,1,1,2,2,7,1,11,11,33,21,7,7,1,1,2,

%U 220,1,1,11,1,1,2,2,1,1,5,1,3,1,1,1,44,7,1,1,2,2,1,11,77,11,11,1,1,1

%N Greatest common divisors of consecutive partition numbers.

%H Amiram Eldar, <a href="/A091719/b091719.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = GCD(A000041(n), A000041(n+1));

%F a(n) = A091717(n+1,n).

%t a[n_] := GCD[PartitionsP[n], PartitionsP[n + 1]]; Array[a, 100, 0] (* _Amiram Eldar_, Apr 30 2020 *)

%t GCD@@#&/@Partition[PartitionsP[Range[0,90]],2,1] (* _Harvey P. Dale_, Nov 22 2023 *)

%o (PARI) a(n) = gcd(numbpart(n), numbpart(n+1)); \\ _Michel Marcus_, Apr 30 2020

%Y Cf. A000041, A091717.

%K nonn

%O 0,9

%A _Reinhard Zumkeller_, Feb 01 2004