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%I #60 Aug 15 2020 09:41:38
%S 220,440,661,881,1105,1325,1546,1766,1991,2211,2432,2652,2876,3096,
%T 3317,3537,3771,3991,4212,4432,4656,4876,5097,5317,5542,5762,5983,
%U 6203,6427,6647,6868,7088,7326,7546,7767,7987,8211,8431,8652,8872,9097,9317,9538
%N Indices of 4's in A090822.
%C Despite appearances, this is a highly irregular sequence. - _N. J. A. Sloane_
%C The first pair of consecutive 4's occurs at position 255895648634818208370064452304769558261700170817472823398081\
%C 655524438021806620809813295008281436789493636145 [Gijswijt, 2016, page 12]. - _Sergio Pimentel_, Feb 21 2017
%C Comment from _N. J. A. Sloane_, Feb 28 2017: (Start)
%C Page 12 of Gijswijt (2016) states:
%C "In dat stuk vinden we 355 promoties en daarmee 355 stukken lijm van lengte 1, 3, 1, 9, 4, 24, 1, 3, ... Na 355 keer verdubbelen en lijm toevoegen vinden we uiteindelijk de eerste dubbele vier in A090822, en wel op positie
%C 255.895.648.634.818.208.370.064.452.304.769.558.
%C 261.700.170.817.472.823.398.081.655.524.438.021.
%C 806.620.809.813.295.008.281.436.789.493.636.145".
%C A rough translation might be:
%C "... we find 355 promotions and thus 355 glue segments of lengths 1, 3, 1, 9, 4, 24, 1, 3, ...
%C We eventually find the first pair of consecutive 4's in A090822 at position
%C 255,895,648,634,818,208,370,064,452,304,769,558,
%C 261,700,170,817,472,823,398,081,655,524,438,021,
%C 806,620,809,813,295,008,281,436,789,493,636,145."
%C _Dion Gijswijt_, Mar 01 2017 adds that the number mentioned is the position of the second 4 in the first occurrence of 4,4 in A090822. For the glue segments see A091579.
%C (End)
%H Charles R Greathouse IV, <a href="/A157107/b157107.txt">Table of n, a(n) for n = 1..300</a>
%H Dion Gijswijt, <a href="https://pyth.eu/uploads/user/ArchiefPDF/Pyth55-3.pdf">Krulgetallen</a>, Pythagoras, 55ste Jaargang, Nummer 3, Jan 2016.
%Y Cf. A090822, A091579.
%K nonn
%O 1,1
%A _Paul Curtz_, Feb 23 2009
%E Edited by _N. J. A. Sloane_, Feb 24 2009
%E More terms from _R. J. Mathar_, Feb 24 2009
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