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A212909
Numbers n such that A212813(n) = 4.
6
17, 26, 29, 31, 33, 35, 38, 42, 44, 49, 50, 51, 52, 57, 58, 60, 62, 64, 65, 68, 70, 72, 73, 77, 78, 79, 81, 84, 85, 88, 89, 91, 95, 99, 100, 102, 103, 105, 106, 107, 110, 112, 114, 116, 119, 120, 121, 124, 125, 126, 128, 129, 130, 132, 135, 142, 143, 144, 146, 147, 150, 154, 156, 160, 162, 170, 175, 177, 178, 180, 182, 184, 192, 195, 196, 197, 202, 204, 205
OFFSET
1,1
REFERENCES
Bellamy, O. S.; Cadogan, C. C. Subsets of positive integers: their cardinality and maximality properties. Proceedings of the Tenth Southeastern Conference on Combinatorics, Graph Theory and Computing (Florida Atlantic Univ., Boca Raton, Fla., 1979), pp. 167--178, Congress. Numer., XXIII-XXIV, Utilitas Math., Winnipeg, Man., 1979. MR0561043 (82b:10006)
LINKS
PROG
(Haskell)
import Data.List (elemIndices)
a212909 n = a212909_list !! (n-1)
a212909_list = map (+ 1) $ elemIndices 4 a212813_list
-- Reinhard Zumkeller, May 30 2012
CROSSREFS
KEYWORD
nonn,fini
AUTHOR
N. J. A. Sloane, May 30 2012
STATUS
approved