Search results
Results From The WOW.Com Content Network
81 is: the square of 9 and the second fourth-power of a prime; 3 4. with an aliquot sum of 40; within an aliquot sequence of three composite numbers (81,40,50,43,1,0) to the Prime in the 43-aliquot tree. a perfect totient number like all powers of three. [1] a heptagonal number. [2] an icosioctagonal number. [3] a centered octagonal number. [4 ...
A square has even multiplicity for all prime factors (it is of the form a 2 for some a). The first: 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144 (sequence A000290 in the OEIS). A cube has all multiplicities divisible by 3 (it is of the form a 3 for some a). The first: 1, 8, 27, 64, 125, 216, 343, 512, 729, 1000, 1331, 1728 (sequence A000578 ...
Trial division and Pollard's rho algorithm can be used to find very small factors of , [125] and elliptic curve factorization can be effective when has factors of moderate size. [153] Methods suitable for arbitrary large numbers that do not depend on the size of its factors include the quadratic sieve and general number field sieve .
Balance factors green; heights red. The keys in the left spine are Fibonacci numbers. The Fibonacci numbers are important in computational run-time analysis of Euclid's algorithm to determine the greatest common divisor of two integers: the worst case input for this algorithm is a pair of consecutive Fibonacci numbers. [72]
Every helpful hint and clue for Sunday's Strands game from the New York Times.
d() is the number of positive divisors of n, including 1 and n itself; σ() is the sum of the positive divisors of n, including 1 and n itselfs() is the sum of the proper divisors of n, including 1 but not n itself; that is, s(n) = σ(n) − n
The entries in the table resolve this ambiguity by the following convention: the factors are primes in the right complex half plane with absolute value of the real part larger than or equal to the absolute value of the imaginary part. The entries are sorted according to increasing norm x 2 + y 2 (sequence A001481 in the OEIS). The table is ...
N is of the form N ≡ 1 (mod 12) or N ≡ 117 (mod 468) or N ≡ 81 (mod 324). [24] The largest prime factor of N is greater than 10 8, [25] and less than . [26] The second largest prime factor is greater than 10 4, [27] and is less than . [28]