A039950 - OEIS

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A039950

Primes of form abs(2*n^2-199).

37, 43, 71, 89, 101, 127, 139, 149, 167, 181, 191, 193, 197, 251, 313, 379, 449, 523, 601, 683, 769, 859, 953, 1051, 1153, 1259, 1483, 1601, 1723, 1979, 2113, 2251, 2393, 2539, 2689, 2843, 3001, 3163, 3329, 3499, 3673, 3851, 4219, 4409, 4603, 4801, 5003

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

REFERENCES

C. Clawson, Mathematical Mysteries, Plenum Press, 1996, p. 173

LINKS

Table of n, a(n) for n=1..47.

MATHEMATICA

Select[Abs[2*Range[-15, 70]^2-199], PrimeQ]//Union (* Harvey P. Dale, Mar 20 2018 *)

PROG

(PARI) isok(n) = isprime(n) && (n != 199) && (issquare((n+199)/2) || issquare((199-n)/2)); \\ Michel Marcus, Sep 28 2013

CROSSREFS