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A145896
Values of m: where m^2 begins a run of consecutive squares satisfying r=p+4*m^2 with a sequence of primes
2
3, 6, 2, 1, 8, 4, 7, 1, 2, 1, 1, 1, 19, 1, 2, 1, 3, 1, 1, 1, 1, 1, 1, 1, 3, 3, 1, 1, 2, 1, 1, 2, 1, 4, 1, 1, 1, 1, 1, 2, 2, 1, 7, 3, 4, 1, 1, 2, 7, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2
OFFSET
1,1
COMMENTS
Suggested by Farideh Firoozbakht's Puzzle 464 in Carlos Rivera's The Prime Puzzles & Problems Connection
EXAMPLE
a(1)=3 because when m is 3 a sequence of three values of r end with prime 37; then r=1+4*1^1=5, prime; and r=1+4*2^2=17, prime; and r=1+4*3^2=37, prime (and the next value of m, 4, does not produce a prime because r=1+4*4^2=65). For this one value 1 is assumed prime.
PROG
(UBASIC) 10 'p464 20 N=1 30 A=3:S=sqrt(N) 40 B=N\A 50 if B*A=N then 100 60 A=A+2 70 if A<=S then 40 80 M=M+1:R=N+4*M^2:if R=prmdiv(R) and M<100 then print N; R; M:goto 80 90 if M>=1 then stop 100 M=0:N=N+2:goto 30
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Oct 25 2008
STATUS
approved