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A108570 Squares of lesser of twin primes. 6
9, 25, 121, 289, 841, 1681, 3481, 5041, 10201, 11449, 18769, 22201, 32041, 36481, 38809, 51529, 57121, 72361, 78961, 96721, 120409, 175561, 185761, 212521, 271441, 323761, 358801, 380689, 410881, 434281, 654481, 674041, 683929, 734449, 776161 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Squares of the form prime(n)*prime(n+1) - 2*prime(n).

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MAPLE

ZL:=[]:for p from 1 to 950 do if (isprime(p) and isprime(p+2)) then ZL:=[op(ZL), (p^2)]; fi; od; print(ZL); # Zerinvary Lajos, Mar 08 2007

MATHEMATICA

Select[First[#]Last[#]-2First[#]&/@Partition[Prime[Range[500]], 2, 1], IntegerQ[ Sqrt[#]]&] (* Harvey P. Dale, May 24 2011 *)

PROG

(PARI) p=2; forprime(q=3, , if(q-p==2, print1(p^2", ")); p=q) \\ Charles R Greathouse IV, Dec 16 2019

(MAGMA) [p^2 : p in PrimesUpTo(1100)| IsPrime(p+2)]; // Vincenzo Librandi, Dec 23 2019

CROSSREFS

Subsequence of A330477.

Cf. A001359, A108604.

Sequence in context: A193644 A083100 A084058 * A092769 A263951 A139818

Adjacent sequences:  A108567 A108568 A108569 * A108571 A108572 A108573

KEYWORD

easy,nonn

AUTHOR

Giovanni Teofilatto, Jul 05 2005

EXTENSIONS

Extended by Ray Chandler, Jul 10 2005

Name and comment swapped by Charles R Greathouse IV, Dec 16 2019

STATUS

approved

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Last modified July 15 15:15 EDT 2020. Contains 335774 sequences. (Running on oeis4.)