Question

prime triangular number is
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Answer 1

Answer:

This works except for all n>2, hence 3 is the only prime triangular number. The only number that is triangle and prime is 3. The triangle numbers can be generated from T=2n2±n=n(2n±1) so that when n=1, triangle number 3 is generated, and when n=2, triangle numbers 6 and 10 are generated, etc.

Answer 2

Answer:

This works except for all n>2, hence 3 is the only prime triangular number. The only number that is triangle and prime is 3. The triangle numbers can be generated from T=2n2±n=n(2n±1) so that when n=1, triangle number 3 is generated, and when n=2, triangle numbers 6 and 10 are generated, etc.