cp's OEIS Frontend

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.

A307295 If n is even, a(n) = A001950(n/2+1), otherwise a(n) = A001950((n-1)/2+1) + 1.

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%I A307295 #24 Aug 11 2022 03:19:45
%S A307295 2,3,5,6,7,8,10,11,13,14,15,16,18,19,20,21,23,24,26,27,28,29,31,32,34,
%T A307295 35,36,37,39,40,41,42,44,45,47,48,49,50,52,53,54,55,57,58,60,61,62,63,
%U A307295 65,66,68,69,70,71,73,74,75,76,78,79,81,82,83,84,86,87,89,90,91,92,94,95,96,97,99,100,102,103,104,105
%N A307295 If n is even, a(n) = A001950(n/2+1), otherwise a(n) = A001950((n-1)/2+1) + 1.
%C A307295 It follows from the definition that a(2i+1) = a(2i)+1 for all i.
%C A307295 From _Jeffrey Shallit_, Jun 06 2021: (Start)
%C A307295 This sequence consists of the nonzero distances between occurrences of 1 in the Fibonacci word A003849 (easily provable with the Walnut theorem-prover).
%C A307295 Alternatively, these are the positive n such that A003849(n-1) = 1 or A003849(n-2) = 1 (again, easily provable with the Walnut theorem-prover). (End)
%D A307295 Eric Friedman, Scott M. Garrabrant, Ilona K. Phipps-Morgan, A. S. Landsberg and Urban Larsson, Geometric analysis of a generalized Wythoff game, in Games of no Chance 5, MSRI publ. Cambridge University Press, date? [See Omega, a few lines below Table 2.]
%o A307295 (Python)
%o A307295 from math import isqrt
%o A307295 def A307295(n): return ((m:=(n>>1)+1)+isqrt(5*m**2)>>1)+m+(n&1) # _Chai Wah Wu_, Aug 10 2022
%Y A307295 Cf. A000201, A001950, A307294.
%K A307295 nonn
%O A307295 0,1
%A A307295 _N. J. A. Sloane_, Apr 12 2019