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Revision History for A155185 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing all changes.
#8 by N. J. A. Sloane at Tue Feb 11 12:13:38 EST 2020
STATUS

reviewed

approved

#7 by Bruno Berselli at Tue Feb 11 12:05:43 EST 2020
STATUS

proposed

reviewed

#6 by Michel Marcus at Tue Feb 11 11:00:15 EST 2020
STATUS

editing

proposed

#5 by Michel Marcus at Tue Feb 11 11:00:10 EST 2020
MATHEMATICA

lst={}; Do[p=n; q=p+1; a=q^2-p^2; c=q^2+p^2; b=2*p*q; ar=a*b/2; s=a+b+c; If[PrimeQ[s-1]&&PrimeQ[s+1], If[PrimeQ[c], AppendTo[lst, c]]], {n, 8!}]; lst (* corrected by _Ray Chandler_, Feb 11 2020 *)

EXTENSIONS

Sequence corrected after second term and program corrected by Ray Chandler, Feb 11 2020

STATUS

proposed

editing

#4 by Ray Chandler at Tue Feb 11 10:42:23 EST 2020
STATUS

editing

proposed

#3 by Ray Chandler at Tue Feb 11 10:41:34 EST 2020
DATA

5, 13, 841, 113, 1741, 3961, 5101, 8581, 276025, 289561, 711625, 2906461, 3545785, 9941, 21841, 26681, 47741, 82013, 481181, 501001, 1009621, 2356621, 2542513, 3279361, 3723721, 4533061, 5187421, 5284501, 5947801, 11286001, 19052965, 21773401, 23344945, 26129221, 37575781, 41032741, 43459165, 45324721, 472294814277813, 7757861, 8124481, 13204661, 25311613, 30772013, 44170601, 48619661, 51521401, 52541501, 54236113, 60731221, 72902813

MATHEMATICA

lst={}; Do[p=n; q=p+1; a=q^2-p^2; c=q^2+p^2; b=2*p*q; ar=a*b/2; s=a+b+c; If[PrimeQ[s-1]&&PrimeQ[s+1], If[PrimeQ[ac], AppendTo[lst, c]]], {n, 8!}]; lst

EXTENSIONS

Sequence corrected after second term and program corrected by Ray Chandler, Feb 11 2020

STATUS

approved

editing

#2 by Russ Cox at Sat Mar 31 12:38:20 EDT 2012
AUTHOR

_Vladimir Joseph Stephan Orlovsky (4vladimir(AT)gmail.com), _, Jan 21 2009

Discussion
Sat Mar 31
12:38
OEIS Server: https://oeis.org/edit/global/876
#1 by N. J. A. Sloane at Fri Feb 27 03:00:00 EST 2009
NAME

Primes in A155175.

DATA

5, 13, 841, 1741, 3961, 5101, 8581, 276025, 289561, 711625, 2906461, 3545785, 3723721, 4533061, 5187421, 5284501, 5947801, 11286001, 19052965, 21773401, 23344945, 26129221, 37575781, 41032741, 43459165, 45324721, 47229481

OFFSET

1,1

COMMENTS

Hypotenuse C (prime numbers only) of primitive Pythagorean triangles such that perimeters are Averages of twin prime pairs, q=p+1, a=q^2-p^2, c=q^2+p^2, b=2*p*q, ar=a*b/2; s=a+b+c, s-+1 are primes. p=1,q=2,a=3,b=4,c=5=prime,s=12-+1primes, ...

MATHEMATICA

lst={}; Do[p=n; q=p+1; a=q^2-p^2; c=q^2+p^2; b=2*p*q; ar=a*b/2; s=a+b+c; If[PrimeQ[s-1]&&PrimeQ[s+1], If[PrimeQ[a], AppendTo[lst, c]]], {n, 8!}]; lst

KEYWORD

nonn

AUTHOR

Vladimir Orlovsky (4vladimir(AT)gmail.com), Jan 21 2009

STATUS

approved