43 (number)


43 is the natural number following 42 and preceding 44.

In mathematics

Forty-three is the 14th smallest prime number. The previous is forty-one, with which it comprises a twin prime, and the next is forty-seven. 43 is the smallest prime that is not a Chen prime. It is also the third Wagstaff prime.
43 is the fourth term of Sylvester's sequence, one more than the product of the previous terms.
43 is a centered heptagonal number.
Let a = a = 1, and thenceforth a =. This sequence continues 1, 1, 2, 3, 5, 10, 28, 154.... a is the first term of this sequence that is not an integer.
43 is a Heegner number.
43 is the largest prime which dives the order of the Janko group J4.
43 is a repdigit in base 6.
43 is the number of triangles inside the Sri Yantra.
43 is the largest natural number that is not a McNugget number.
43 is the smallest prime number expressible as the sum of 2, 3, 4, or 5 different primes:
When taking the first six terms of the Taylor series for computing e, one obtains
which is also five minus the fifth harmonic number.
Every solvable configuration of the Fifteen puzzle can be solved in no more than 43 multi-tile moves.

In science

In auto racing:

Music

Forty-three is: