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A118593 Larger component of twin prime pairs whose sum is a square. 2
19, 73, 883, 1153, 2593, 3529, 4051, 15139, 20809, 34849, 46819, 69193, 83233, 103969, 112339, 149059, 176419, 180001, 206083, 281251, 362953, 388963, 438049, 472393, 478243, 538723, 649801, 734473, 808993, 960499, 1080451, 1143073 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also A069496(n)+2.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..180

Author?, Title? (broken link)

EXAMPLE

17 and 19 are twin primes whose sum is 36, a square, so 19 is the first term in the table.

MATHEMATICA

Transpose[Select[Partition[Prime[Range[200000]], 2, 1], #[[2]]-#[[1]]==2 && IntegerQ[Sqrt[Total[#]]]&]][[2]] (* Harvey P. Dale, Jul 29 2014 *)

PROG

(PARI) g(n) = for(x=1, n, p1=prime(x); p2=prime(x+1); if(p2-p1==2&issquare(p1+p2), print1(p2", ")))

CROSSREFS

Cf. A069496 and A118593.

Sequence in context: A255897 A220447 A294460 * A047979 A290241 A159997

Adjacent sequences:  A118590 A118591 A118592 * A118594 A118595 A118596

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard, May 08 2006

STATUS

approved

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Last modified August 18 04:50 EDT 2019. Contains 326072 sequences. (Running on oeis4.)