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A334121 a(n) is the multiplicative inverse of A008514(n) modulo A008514(n+1).

%I A334121 #16 Jun 05 2020 16:54:38
%S A334121 1,40,271,183,1184,102,2861,9102,4446,16837,3483,25332,62253,30739,
%T A334121 88410,26394,111803,2177,123512,298353,110585,346624,55398,366215,
%U A334121 782616,335806,866645,228189,893798,9628,832307,1873716,643300,1905211,280161,1793338,3647187
%N A334121 a(n) is the multiplicative inverse of A008514(n) modulo A008514(n+1).
%o A334121 (PARI)
%o A334121 f(n) = n^4 + (n+1)^4; \\ A008514
%o A334121 a(n) = lift(1/Mod(f(n), f(n+1)));
%o A334121 (Python)
%o A334121 import gmpy2
%o A334121 soc = [] # sum of 4d-centered cubes
%o A334121 a=0
%o A334121 b=1
%o A334121 for i in range(100):
%o A334121     c = a**4 + b**4
%o A334121     soc.append(c)
%o A334121     a += 1
%o A334121     b += 1
%o A334121 A334121 = []
%o A334121 for i in range(len(soc)-1):
%o A334121     c = gmpy2.invert(soc[i], soc[i+1])
%o A334121     A334121.append(int(c))
%o A334121 print(', '.join([str(x) for x in A334121]))
%Y A334121 Cf. A008514, A308215, A308217, A334137.
%K A334121 nonn
%O A334121 0,2
%A A334121 _Daniel Hoyt_, Apr 14 2020