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%I #13 Jan 06 2025 04:08:19
%S 1,601,252,403,455,202,131,105,107,330,237,306,387,606,285,261,316,
%T 557,170,240,512,562,147,210,150,87,295,293,380,35,582,571,349,541,
%U 230,621,436,295,24,275,442,212,542,511,560,222,371,147,418,150,257,336,552,420
%N Ramanujan numbers (A000594) read mod 625.
%H Seiichi Manyama, <a href="/A126835/b126835.txt">Table of n, a(n) for n = 1..10000</a>
%H H. P. F. Swinnerton-Dyer, <a href="http://dx.doi.org/10.1007/978-3-540-37802-0_1">On l-adic representations and congruences for coefficients of modular forms</a>, pp. 1-55 of Modular Functions of One Variable III (Antwerp 1972), Lect. Notes Math., 350, 1973.
%t a[n_] := Mod[RamanujanTau[n], 625]; Array[a, 100] (* _Amiram Eldar_, Jan 05 2025 *)
%o (PARI) a(n) = ramanujantau(n) % 625; \\ _Amiram Eldar_, Jan 05 2025
%Y Cf. A000594, A126832 (mod 5^1), A126833 (mod 5^2), A126834 (mod 5^3), this sequence (mod 5^4).
%K nonn,changed
%O 1,2
%A _N. J. A. Sloane_, Feb 25 2007