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A192687 Male-female differences: a(n) = A005378(n) - A005379(n). 3
1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0

COMMENTS

0 <= a(n) <= 1;

for n > 0: a(n) = A010056(n-1), a(A001690(n)-1) = 0, a(A000071(n)) = 1.

REFERENCES

Hofstadter, "Goedel, Escher, Bach", p. 137.

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 0..10000

Eric Weisstein's World of Mathematics,Hofstadter Male-Female Sequences.

Index entries for Hofstadter-type sequences

Index entries for sequences from "Goedel, Escher, Bach"

PROG

(Haskell)

a192687 n = a192687_list !! n

a192687_list = zipWith (-) females males where

   females = 1 : zipWith (-) [1..] (map (males !!) females)

   males = 0 : zipWith (-) [1..] (map (females !!) males)

(PARI) a(n)=my(k=(n+1)^2); k+=(k+1)<<2; issquare(k) || issquare(k-8) \\ Charles R Greathouse IV, Nov 07 2014

CROSSREFS

Cf. A104162.

Sequence in context: A093709 A079295 A088025 * A189141 A082416 A093996

Adjacent sequences:  A192684 A192685 A192686 * A192688 A192689 A192690

KEYWORD

nonn,easy

AUTHOR

Reinhard Zumkeller, Jul 12 2011

STATUS

approved

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Last modified June 17 17:12 EDT 2019. Contains 324196 sequences. (Running on oeis4.)