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Revision History for A270005

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A270005

Integers n such that 1^2 + 3^2 + 5^2 + ... + (2*n-1)^2 = x^3 + y^3 has a solution in positive integers x and y.
(history; published version)

#13 by Michel Marcus at Thu Mar 17 05:59:23 EDT 2016

STATUS

reviewed

approved

#12 by Joerg Arndt at Thu Mar 17 05:28:55 EDT 2016

STATUS

proposed

reviewed

#11 by Chai Wah Wu at Wed Mar 16 21:41:09 EDT 2016

STATUS

editing

proposed

#10 by Chai Wah Wu at Wed Mar 16 21:15:04 EDT 2016

DATA

3, 48, 813, 4697, 5694, 6752, 13773, 25477, 34989, 125632, 233328, 362313, 605634, 673464, 691659, 941896, 3654841, 3952803, 5024551, 5619712, 6509427, 10833183, 12473149

EXTENSIONS

a(10)-a(23) from Chai Wah Wu, Mar 16 2016

STATUS

approved

editing

#9 by N. J. A. Sloane at Fri Mar 11 06:26:43 EST 2016

STATUS

editing

approved

#8 by N. J. A. Sloane at Fri Mar 11 06:26:30 EST 2016

NAME

Integers n such that 1^2 + 3^2 + 5^2 + ... + (2*n-1)^2 = x^3 + y^3 has a solution forin positive integers x and y.

STATUS

proposed

editing

Discussion
Fri Mar 11	06:26	N. J. A. Sloane: edited definition

#7 by Altug Alkan at Tue Mar 08 18:56:52 EST 2016

STATUS

editing

proposed

#6 by Altug Alkan at Tue Mar 08 18:55:47 EST 2016

CROSSREFS

Cf. A000447, A003325, A269842.

#5 by Altug Alkan at Tue Mar 08 18:45:09 EST 2016

EXAMPLE

48 is a term because 1^2 + 3^2 + 5^2 + ... + 95^2 = 31^3 + 49^3.

#4 by Altug Alkan at Tue Mar 08 18:41:12 EST 2016

PROG

(PARI)) isA003325(n) = for(k=1, sqrtnint(n\2, 3), ispower(n-k^3, 3) && return(1));

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Last modified August 18 20:50 EDT 2024. Contains 375284 sequences. (Running on oeis4.)