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Revision History for A286595

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Compound filter (2-adic valuation & deficiency/abundance): a(n) = P(A001511(n), A286449(n)), where P(n,k) is sequence A000027 used as a pairing function.
(history; published version)

#8 by N. J. A. Sloane at Sun May 21 23:59:43 EDT 2017

STATUS

proposed

approved

#7 by Antti Karttunen at Sun May 21 23:44:08 EDT 2017

STATUS

editing

proposed

#6 by Antti Karttunen at Sun May 21 22:51:18 EDT 2017

CROSSREFS

Cf. A000027, A001511, A033879, A033880, A286449, A286260, A286451, A286460, A286592, A286593.

Discussion

Sun May 21

23:32

Antti Karttunen: A longish data-section on purpose (not that many duplicated terms, and 407 is one of them).

#5 by Antti Karttunen at Sun May 21 22:49:55 EDT 2017

CROSSREFS

Cf. A000027, A001511, A033879, A033880, A286449, A286451, A286460, A286592, A286593.

#4 by Antti Karttunen at Sun May 21 22:48:31 EDT 2017

LINKS

Antti Karttunen, <a href="/A286595/b286595.txt">Table of n, a(n) for n = 1..10000</a>

#3 by Antti Karttunen at Sun May 21 22:44:11 EDT 2017

CROSSREFS

Cf. A000027, A001511, A033879, A033880, A286449, A286592, A286593.

#2 by Antti Karttunen at Sun May 21 22:41:40 EDT 2017

NAME

allocated for Antti KarttunenCompound filter (2-adic valuation & deficiency/abundance): a(n) = P(A001511(n), A286449(n)), where P(n,k) is sequence A000027 used as a pairing function.

DATA

1, 3, 2, 6, 4, 12, 11, 10, 16, 5, 22, 48, 37, 8, 11, 15, 46, 68, 67, 108, 22, 107, 106, 175, 137, 30, 154, 18, 172, 138, 191, 21, 67, 173, 106, 256, 232, 57, 106, 329, 277, 138, 301, 13, 37, 353, 352, 501, 407, 467, 191, 24, 466, 138, 497, 634, 562, 632, 631, 744, 704, 192, 106, 28, 352, 138, 742, 39, 301, 38, 781, 950, 862, 597, 596, 58, 631, 138, 904, 1133, 407

OFFSET

1,2

LINKS

Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PairingFunction.html">Pairing Function</a>

FORMULA

a(n) = (1/2)*(2 + ((A001511(n)+A286449(n))^2) - A001511(n) - 3*A286449(n)).

PROG

(Scheme) (define (A286595 n) (* (/ 1 2) (+ (expt (+ (A001511 n) (A286449 n)) 2) (- (A001511 n)) (- (* 3 (A286449 n))) 2)))

CROSSREFS

Cf. A000027, A001511, A286449, A286592, A286593.

KEYWORD

allocated

nonn

AUTHOR

Antti Karttunen, May 21 2017

STATUS

approved

editing

#1 by Antti Karttunen at Thu May 11 12:51:34 EDT 2017

NAME

allocated for Antti Karttunen

KEYWORD

allocated

STATUS

approved