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A099728 Least number B such that (A001359(n) - B^2)^2 - B is also the lesser of larger twin primes, or 0 if no such B exists. 1
380, 14, 5, 5, 365, 8, 5, 5, 14, 20, 5, 20, 8, 65, 8, 95, 35, 8, 14, 65, 20, 65, 8, 17, 350, 188, 5, 104, 98, 68, 35, 17, 158, 35, 92, 50, 62, 5, 26, 8, 8, 68, 233, 110, 5, 50, 23, 23, 8, 65, 59, 35, 14, 23, 35, 20, 47, 140, 5, 50, 14, 5, 4, 4, 125, 386, 713, 23, 59, 44, 635, 98 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Conjecture: No term is zero.

LINKS

Table of n, a(n) for n=1..72.

EXAMPLE

a(3)=5. A001359(3)=11. 11 and 13 are twin primes. (11-5^2)^2 - 5 = 191. 191 and 193 are also twin primes.

MAPLE

a135 := [] : f := fopen("b001359.txt", READ) : while nops(a135) < 200 do l := fscanf(f, "%d %d") : if l = [] then break : else a135 := [op(a135), l[2]] : fi ; od : for n from 1 to nops(a135) do a := op(n, a135) : B := 0 : while true do srch := (a-B^2)^2-B ; if isprime(srch) and isprime(srch+2) and srch > a then printf("%d, ", B) ; break ; fi ; B := B+1 : od : od: # R. J. Mathar, Aug 06 2007

CROSSREFS

Sequence in context: A133961 A133962 A027503 * A206349 A252130 A252123

Adjacent sequences:  A099725 A099726 A099727 * A099729 A099730 A099731

KEYWORD

nonn

AUTHOR

Ray G. Opao, Nov 07 2004

EXTENSIONS

Corrected and extended by R. J. Mathar, Aug 06 2007

STATUS

approved

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Last modified December 11 03:18 EST 2016. Contains 279034 sequences.