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Revision History for A182312

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A182312

Primes of the form a^2 + b^2 such that both a^2 + b^2 - a*b and a^2 + b^2 + a*b are prime.
(history; published version)

#26 by Bruno Berselli at Tue Mar 13 05:39:21 EDT 2018

STATUS

reviewed

approved

#25 by Joerg Arndt at Tue Mar 13 05:38:05 EDT 2018

STATUS

proposed

reviewed

#24 by Thomas Ordowski at Tue Mar 13 03:05:02 EDT 2018

STATUS

editing

proposed

#23 by Thomas Ordowski at Tue Mar 13 03:04:52 EDT 2018

FORMULA

a(n) == 1 (mod 4). - _Thomas Ordowski_, Mar 13 2018

STATUS

proposed

editing

#22 by Thomas Ordowski at Tue Mar 13 02:24:08 EDT 2018

STATUS

editing

proposed

Discussion

Tue Mar 13

02:43

Michel Marcus: ok thanks; please sign new formula

#21 by Thomas Ordowski at Tue Mar 13 02:23:57 EDT 2018

FORMULA

a(n) == 1 (mod 4).

STATUS

proposed

editing

#20 by Thomas Ordowski at Tue Mar 13 02:18:15 EDT 2018

STATUS

editing

proposed

#19 by Thomas Ordowski at Tue Mar 13 02:17:56 EDT 2018

FORMULA

The prime 13 = 2^2 + 3^2 is a term, since 13 - 2*3 = 7 is prime and 13 + 2*3 = 19 is prime.

EXAMPLE

The prime 13 = 2^2 + 3^2 is a term, since 13 - 2*3 = 7 is prime and 13 + 2*3 = 19 is prime.

Discussion

Tue Mar 13

02:18

Thomas Ordowski: Done.

#18 by Thomas Ordowski at Tue Mar 13 02:10:41 EDT 2018

NAME

Primes of the form a^2 + b^2 such that both a^2 + b^2 - a*b and a^2 + b^2 + a*b are primesprime.

FORMULA

The prime 13 = 2^2 + 3^2 is a term, since 13 - 2*3 = 7 is prime and 13 + 2*3 = 19 is prime.

CROSSREFS

Subsequence of A002313.

Cf. A002313, A007645.

STATUS

reviewed

editing

#17 by Robert G. Wilson v at Mon Mar 12 14:38:33 EDT 2018

STATUS

proposed

reviewed

Discussion

Mon Mar 12

18:12

Michel Marcus: Rather?  Subsequence of  A002313. Cf. A007645. And can you add an example