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A154756
Primes p such that ratio in A154754 is 3.
2
7, 13, 19, 61, 73, 79, 103, 109, 127, 139, 151, 163, 193, 199, 211, 241, 271, 307, 337, 349, 373, 409, 421, 523, 541, 547, 571, 607, 613, 673, 739, 757, 769, 787, 811, 853, 877, 883, 907, 919, 937, 967, 991, 1009, 1033, 1063, 1087, 1117, 1123, 1129, 1201
OFFSET
1,1
COMMENTS
Note that all these primes have the form 6k+1, which is required for the equation x^2+x+1=0 (mod p) to have two integer solutions. However, this sequence has only about half of all 6k+1 primes. What other condition determines the p in this sequence? See A154755 for the primes not in this sequence.
CROSSREFS
Sequence in context: A231506 A165724 A144232 * A024732 A024954 A373544
KEYWORD
nonn
AUTHOR
T. D. Noe, Jan 15 2009
STATUS
approved