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 A176415 #24 Jan 01 2023 02:29:09 %S A176415 7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1, %T A176415 7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1, %U A176415 7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7,1,7 %N A176415 Periodic sequence: repeat 7,1. %C A176415 Interleaving of A010727 and A000012. %C A176415 Also continued fraction expansion of (7+sqrt(77))/2. %C A176415 Also decimal expansion of 71/99. %C A176415 Essentially first differences of A047521. %C A176415 Binomial transform of A176414. %C A176415 Inverse binomial transform of 2*A020707 preceded by 7. %C A176415 Exp( Sum_{n >= 1} a(n)*x^n/n ) = 1 + x + 4*x^2 + 4*x^3 + 10*x^4 + 10*x^5 + ... is the o.g.f. for A058187. - _Peter Bala_, Mar 13 2015 %H A176415 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0,1). %F A176415 a(n) = 4+3*(-1)^n. %F A176415 a(n) = a(n-2) for n > 1; a(0) = 7, a(1) = 1. %F A176415 a(n) = -a(n-1)+8 for n > 0; a(0) = 7. %F A176415 a(n) = 7*((n+1) mod 2)+(n mod 2). %F A176415 a(n) = A010688(n+1). %F A176415 G.f.: (7+x)/(1-x^2). %F A176415 Dirichglet g.f.: (1+6*2^(-s))*zeta(s). - _R. J. Mathar_, Apr 06 2011 %F A176415 Multiplicative with a(2^e) = 7, and a(p^e) = 1 for p >= 3. - _Amiram Eldar_, Jan 01 2023 %t A176415 PadRight[{},120,{7,1}] (* _Harvey P. Dale_, Dec 30 2018 *) %o A176415 (Magma) &cat[ [7, 1]: n in [0..52] ]; %o A176415 [ 4+3*(-1)^n: n in [0..104] ]; %o A176415 (PARI) a(n)=7-n%2*6 \\ _Charles R Greathouse IV_, Oct 28 2011 %Y A176415 Cf. A010727 (all 7's sequence), A000012 (all 1's sequence), A092290 (decimal expansion of (7+sqrt(77))/2), A010688 (repeat 1, 7), A047521 (congruent to 0 or 7 mod 8), A176414 (expansion of (7+8*x)/(1+2*x)), A020707 (2^(n+2)), A058187. %K A176415 cofr,cons,easy,nonn,mult %O A176415 0,1 %A A176415 _Klaus Brockhaus_, Apr 17 2010