Search: id:A109769 Results 1-1 of 1 results found. %I A109769 %S A109769 18,25,133,2107,4676,226037,4477739,827867201 %N A109769 Composite n such that binomial(7*n, n) == 7^n (mod n). %C A109769 No other terms below 10^9. %H A109769 Max Alekseyev, PARI/GP scripts for various problems %e A109769 18 is a term because binomial(7*18, 18) = 2797093093529137508875, 7^18 = 1628413597910449 and 2797093093529137508875 mod 18 = 1628413597910449 mod 18 = 1. %t A109769 Do[If[ !PrimeQ[n], If[Mod[Binomial[7*n, n], n] == Mod[7^n, n], Print[n]]], {n, 2, 20000}] %Y A109769 Cf. A080469. %Y A109769 Sequence in context: A072422 A003300 A084379 this_sequence A093018 A167336 A003634 %Y A109769 Adjacent sequences: A109766 A109767 A109768 this_sequence A109770 A109771 A109772 %K A109769 more,nonn,new %O A109769 1,1 %A A109769 Ryan Propper (rpropper(AT)stanford.edu), Aug 13 2005 %E A109769 226037 from Max Alekseyev (maxale(AT)gmail.com), Sep 13 2009 %E A109769 Two more terms from Max Alekseyev (maxale(AT)gmail.com), Nov 06 2009 Search completed in 0.001 seconds