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A245463
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Smallest k such that A002522(k) and A002522(k+2n) are successive primes of the form m^2+1.
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1
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2, 6, 84, 66, 26, 134, 40, 94, 986, 184, 1524, 716, 864, 1246, 2986, 784, 350, 2174, 4796, 496, 7674, 13136, 3390, 12636, 5880, 9904, 16446, 37410, 6646, 10430, 56774, 31870, 9054, 24606, 12986, 54284, 35000, 124320, 114216, 58576, 88854, 85416, 18854, 3536
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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a(3) = 84 because A002522(84)=7057 and A002522(84+2*3)= 8101 are two consecutive primes of the form m^2+1.
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MAPLE
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T:=array(1..44):
for n from 1 by 2 to 88 do:
z:=0:ii:=0:
for k from 2 to 10^7 while(z=0) do:
p:=k^2+1:
if type(p, prime)=false
then
ii:=ii+1:
else
if ii=n
then
printf ( "%d %d \n", (n+1)/2, k-n-1):T[(n+1)/2]:=k-n-1:z:=1:
else
fi:
ii:=0:
fi:
od:
od:
print(T):
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PROG
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(PARI) for(n=1, 44, m=2; until(m==k+2*n, k=m; until(isprime(m^2+1), m++)); print1(k", ")) \\ Jens Kruse Andersen, Jul 22 2014
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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