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A220348 Index of row where n occurs in A183079.

%I A220348 #25 Jun 06 2025 19:16:51
%S A220348 1,2,3,3,4,4,4,5,5,4,5,6,6,5,5,6,7,7,6,6,5,7,8,8,7,7,6,5,8,9,9,8,8,7,
%T A220348 6,6,9,10,10,9,9,8,7,7,6,10,11,11,10,10,9,8,8,7,5,11,12,12,11,11,10,9,
%U A220348 9,8,6,6,12,13,13,12,12,11,10,10,9,7,7,7,13
%N A220348 Index of row where n occurs in A183079.
%C A220348 A183079 seen as flattened sequence is a permutation of the natural numbers, therefore for each n there exists exactly 1 row in A183079 containing n.
%C A220348 In this sequence each n >= 2 occurs a total of 2^(n-2) times. - _Antti Karttunen_, May 18 2015
%H A220348 Reinhard Zumkeller (first 250 terms) &  Antti Karttunen, <a href="/A220348/b220348.txt">Table of n, a(n) for n = 1..10440</a>
%F A220348 a(n) = 1 + A029837(A220347(n)) = A070941(A220347(n)-1). - _Antti Karttunen_, May 18 2015
%t A220348 (* b is A220347 *) b[n_] := b[n] = With[{r = (-1 + Sqrt[8n + 1])/2}, Which[n <= 1, n, IntegerQ[r], 2b[Floor[Sqrt[2n] + 1/2]] - 1, True, 2b[n - Floor[r]]]];
%t A220348 a[n_] := 1 + IntegerLength[b[n] - 1, 2];
%t A220348 Array[a, 100] (* _Jean-François Alcover_, Dec 05 2021 *)
%o A220348 (Haskell)
%o A220348 import Data.List (findIndex)
%o A220348 import Data.Maybe (fromJust)
%o A220348 a220348 n = fromJust (findIndex (elem n) a183079_tabf) + 1
%o A220348 (Scheme)
%o A220348 (define (A220348 n) (+ 1 (A029837 (A220347 n))))
%o A220348 ;; _Antti Karttunen_, May 18 2015
%o A220348 (Scheme)
%o A220348 (define (A220348 n) (A070941 (+ -1 (A220347 n))))
%o A220348 ;; _Antti Karttunen_, May 18 2015
%Y A220348 Cf. A029837, A070941, A183079, A220347.
%K A220348 nonn
%O A220348 1,2
%A A220348 _Reinhard Zumkeller_, Dec 12 2012
%E A220348 Name edited by _Michel Marcus_, Jan 26 2022