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%I #9 Aug 12 2020 01:29:07
%S 6,6,30,30,282,2262,17034,36006,71070
%N Minimal value of A007947(m*(7^n-m)) with m coprime to 7.
%C The minima are reached for m values given in A147804.
%C This is related to the abc conjecture.
%C All terms of this sequence are even, so one could also consider A147799/2 = 3, 3, 15, 15, 141, 1131, 8517, 18003, 35535, ... So far these terms are also multiples of 3, but this might be a coincidence.
%o (PARI) A147799(n,p=7)={my(m=n=p^n); for(a=1,n\2, a%p || next; m > 2*A007947(a) || next; m > A007947(n-a)*A007947(a) || next; m = A007947(n-a)*A007947(a)); m; }
%Y Cf. A007947, A147804 (m values); A143702, A147801, A147800 (analog for 2^n, 3^n, 5^n), A147298 (general case).
%K nonn,more
%O 1,1
%A _M. F. Hasler_, Nov 13 2008
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