MathBabbler created a nBAB for the number 77 on 29 March 2009. While working on that nBAB, he learned that 77 was a Ruth-Aaron pair with

`. On 31 March 2009, MathBabbler and his CSC100 class wrote a C program that determines if a number is a member of the Ruth-Aaron pair. This nBAB about the number`

78`is the first nBAB to use the MBNA's Ruth-Aaron program.`

78MathBabbler Number Analyst (MBNA) output: ========================================= 78 is a natural, whole, integer 78 is even 78 proper divisors are: 1,2,3,6,13,26,39, 78 is abundant (sum of divisors is 90) 78 is unhappy 78 is not a Harshad number 78 is not prime 78 has the prime factors: 2*3*13 78 is sphenic (had 3 unique prime factors) 78 sum prime factors: 2...3...13...answer: 18 78 is undulating 78 and 77 are a Ruth-Aaron pair 78 and 77 are a Ruth-Aaron pair (distinct prime factors) 78 in octal is 0116 78 in hexadecimal is 0x4e 78 in binary is 1001110 (is evil) 78 nearest square numbers: -14...3 (64...81 [9]) sqrt(78) = 8.83176 ln(78) = 4.35671 log(78) = 1.89209 78 reciprocal is .01282051282051282051282051282051 78! is 1.13243e+115 78 is 24.8282 Pi years 78 is 3 score and 18 years 78 written as a Roman numeral is LXXVIII

`[Wikipedia]`

`is a triangular number. A`

78triangular numberis the "number of dots in an equilateral triangle evenly filled with dots. For example, three dots can be arranged in a triangle; thus three is a triangle number."On 2 April 2009, when this nBAB was created, the MBNA was not checking from triangular numbers.

OEIS.org::id:A000217

## Update::2009.10.04

Pavel Popovich, the 6th man to orbit Earth, died on 29 September 2009 at the age of

`.`

78

`approximates Pi rounded to the nearest hundredth.`

log_{4}(78)

`equals repdigit number 99.`

78_{13}BAB created on 4 October 2009... BAB::Pavel Popovich is Dead at 78

**Creator:** Gerald Thurman
[gthurman@gmail.com]

**Created:** 02 April 2009

This work is licensed under a Creative Commons Attribution 3.0 United States License.