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A220348
Index of row where n occurs in A183079.
3
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, 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, 9, 8, 6, 6, 12, 13, 13, 12, 12, 11, 10, 10, 9, 7, 7, 7, 13
OFFSET
1,2
COMMENTS
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.
In this sequence each n >= 2 occurs a total of 2^(n-2) times. - Antti Karttunen, May 18 2015
LINKS
Reinhard Zumkeller (first 250 terms) & Antti Karttunen, Table of n, a(n) for n = 1..10440
FORMULA
a(n) = 1 + A029837(A220347(n)) = A070941(A220347(n)-1). - Antti Karttunen, May 18 2015
MATHEMATICA
(* 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]]]];
a[n_] := 1 + IntegerLength[b[n] - 1, 2];
Array[a, 100] (* Jean-François Alcover, Dec 05 2021 *)
PROG
(Haskell)
import Data.List (findIndex)
import Data.Maybe (fromJust)
a220348 n = fromJust (findIndex (elem n) a183079_tabf) + 1
(Scheme, two variants)
(define (A220348 n) (+ 1 (A029837 (A220347 n))))
(define (A220348 n) (A070941 (+ -1 (A220347 n))))
;; Antti Karttunen, May 18 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Dec 12 2012
EXTENSIONS
Name edited by Michel Marcus, Jan 26 2022
STATUS
approved