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A202342
Numbers occurring exactly twice in Hofstadter H-sequence A005374.
16
1, 4, 5, 7, 10, 13, 14, 17, 18, 20, 23, 24, 26, 29, 32, 33, 35, 38, 41, 42, 45, 46, 48, 51, 54, 55, 58, 59, 61, 64, 65, 67, 70, 73, 74, 77, 78, 80, 83, 84, 86, 89, 92, 93, 95, 98, 101, 102, 105, 106, 108, 111, 112, 114, 117, 120, 121, 123, 126, 129, 130, 133
OFFSET
1,2
COMMENTS
Position of the n-th occurrence of the digit 1 in A105083(n-1) for n>=1. - Jeffrey Shallit, Mar 08 2025
LINKS
Larry Ericksen and Peter G. Anderson, Patterns in differences between rows in k-Zeckendorf arrays, The Fibonacci Quarterly, Vol. 50, No. 1 (February 2012), pp. 11-18.
Jeffrey Shallit, The Narayana Morphism and Related Words, arXiv:2503.01026 [math.CO], 2025.
Eric Weisstein's World of Mathematics, Hofstadter H-Sequence.
FORMULA
A202340(a(n)) = 2.
a(n) = A005374(A136496(n)). - Alan Michael Gómez Calderón, Dec 22 2024
a(n) = A136495(A136495(n)). - Alan Michael Gómez Calderón, Jan 06 2025
PROG
(Haskell)
import Data.List (elemIndices)
a202342 n = a202342_list !! (n-1)
a202342_list = elemIndices 2 a202340_list
CROSSREFS
Cf. A005374, A105083, A202340, A136495, A136496, A202341 (complement).
Sequence in context: A269861 A187479 A013947 * A234141 A093517 A248858
KEYWORD
nonn,changed
AUTHOR
Reinhard Zumkeller, Dec 17 2011
STATUS
approved