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A085003
Partial sums of A085002.
5
1, 2, 2, 2, 2, 3, 4, 4, 4, 4, 5, 6, 7, 7, 7, 8, 9, 10, 10, 10, 11, 12, 13, 13, 13, 13, 14, 15, 15, 15, 15, 16, 17, 18, 18, 18, 19, 20, 21, 21, 21, 22, 23, 24, 24, 24, 24, 25, 26, 26, 26, 26, 27, 28, 28, 28, 28, 29, 30, 31, 31, 31, 32, 33, 34, 34, 34, 34, 35, 36, 36, 36, 36, 37, 38
OFFSET
1,2
LINKS
B. Cloitre, Graph of A085005(n) for n=1 up to 3874 [archive.org link]
FORMULA
a(n)=sum(k=1, n, A085002(k)).
a(A283766(n)) = n for all n >= 1. - Antti Karttunen, Mar 17 2017
MATHEMATICA
Accumulate[Table[Floor[GoldenRatio*n]-2*Floor[GoldenRatio*n/2], {n, 110}]] (* Harvey P. Dale, Dec 11 2012 *)
PROG
(PARI) sum(k=1, n, (k+sqrtint(5*k^2))%4>1) \\ Charles R Greathouse IV, Feb 07 2013
(Scheme, with memoization-macro definec)
(definec (A085003 n) (if (= 1 n) n (+ (A085002 n) (A085003 (- n 1)))))
;; Antti Karttunen, Mar 17 2017
CROSSREFS
Partial sums of A085002. A left inverse of A283766.
Sequence in context: A301426 A194222 A025779 * A119026 A064775 A260731
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jun 17 2003
STATUS
approved