This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A051277 #29 Dec 04 2022 13:06:11 %S A051277 3,1,2,6,1,2,1,2,4,6,6,2,1,1,0,2,1,1,4,6,1,3,2,6,6,3,5,5,6,3,4,5,0,1, %T A051277 6,3,0,4,6,2,4,4,6,4,2,4,4,2,6,1,3,4,1,3,1,4,2,6,6,0,3,5,5,1,1,2,0,6, %U A051277 6,1,1,2,4,4,4,2,3,6,6,3,6,1,4,4,2,2,1,3 %N A051277 Coefficients in 7-adic expansion of sqrt(2). %D A051277 Alf van der Poorten, Notes on Fermat's Last Theorem, Wiley, 1996, p. 76. %H A051277 Seiichi Manyama, <a href="/A051277/b051277.txt">Table of n, a(n) for n = 0..10000</a> %H A051277 Peter Bala, <a href="/A051277/a051277.pdf">Using Chebyshev polynomials to find the p-adic square roots of 2 and 3</a>, Dec 2022. %F A051277 Equals the 7-adic limit as n -> oo of 2*T(7^n,3/2) = the 7-adic limit as n -> oo of ((3 + sqrt(5))/2)^(7^n) + ((3 - sqrt(5))/2)^(7^n), where T(n,x) denotes the n-th Chebyshev polynomial of the first kind. - _Peter Bala_, Nov 20 2022 %e A051277 3 + 7 + 2*7^2 + 6*7^3 + 7^4 + 2*7^5 + 7^6 + ... %p A051277 t := proc(n) option remember; if n = 1 then 3 else irem(t(n-1)^7 - 7*t(n-1)^5 + 14*t(n-1)^3 - 7*t(n-1), 7^n) end if; end: %p A051277 convert(t(100), base, 7); # _Peter Bala_, Nov 20 2022 %o A051277 (PARI) Vecrev(digits(lift(sqrt(2+O(7^99))),7)) \\ _Joerg Arndt_, Aug 05 2017 %Y A051277 Cf. A034945, A290558. %K A051277 nonn,easy,nice %O A051277 0,1 %A A051277 _N. J. A. Sloane_ %E A051277 Missing terms=0 inserted by _Seiichi Manyama_, Aug 04 2017