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Number of partitions satisfying cn(2,5) < cn(1,5) + cn(4,5) and cn(3,5) < cn(1,5) + cn(4,5).
1

%I #9 Feb 19 2021 09:20:29

%S 1,1,1,3,4,6,9,11,17,26,32,46,60,78,111,138,183,236,297,399,489,630,

%T 794,978,1262,1541,1923,2392,2907,3638,4418,5406,6617,7980,9755,11772,

%U 14193,17148,20514,24688,29549,35242,42111,50017,59446

%N Number of partitions satisfying cn(2,5) < cn(1,5) + cn(4,5) and cn(3,5) < cn(1,5) + cn(4,5).

%C For a given partition cn(i,n) means the number of its parts equal to i modulo n.

%C Short: 2 < 1 + 4 and 3 < 1 + 4 (BBMAAp).

%H Charles R Greathouse IV, <a href="/A039889/b039889.txt">Table of n, a(n) for n = 1..100</a>

%o (PARI) has(vs)=my(cn=vector(5)); for(i=1,#vs,cn[vs[i]%5+1]++); cn[3]<cn[2]+cn[5] && cn[4]<cn[2]+cn[5]

%o a(n)=my(s); forpart(p=n,if(has(p),s++)); s \\ _Charles R Greathouse IV_, Feb 18 2021

%K nonn

%O 1,4

%A _Olivier Gérard_