# numbers that are the sum of two squares

This is sequence A001481 in OEIS.
keywords:
[Mathematics]
[Number Theory]
[closed under multiplication]

# On-line Encyclopedia of Integer Sequences (OEIS)

(Online Encyclopedia of Integer Sequences (OEIS))
(online list of integer sequences)
keywords:
[Mathematics]
[integers]
[whole numbers]
[catalog]
[catalogue]

# wisdom teeth

(suggested new terminology)
A wisdom tooth is anything that prevents something from happening. For example, an integer greater than unity is representable as the sum of two squares if, and only if, its prime factorization does not contain a wisdom tooth, a wisdom tooth in this case being a prime congruent to 3 (mod 4) raised to a positive odd power.
keywords: life, Mathematics, Number Theory

# OBSERVATION (molarity)

In the formula for the dependence of molarity on small changes in temperature (because temperature affects volume), the denominator has the same form as the denominator in problem 6 of IMO 1988, that is, is of the form 1 + ab.
keywords: coincidence, similarity, fraction, Chemistry, Physics, Number Theory