# 77

77. Jag har tagit mig ända hit. Trots en av de mest intensiva tider jag någonsin haft. Sjuttiosju – sjuan som det heliga talet: summan blir ”Christ” – men också att sju och alla tal med sjuor räknas som perfekta jämfört med sexor. 77. Det år som jag började skolan. Det år som mina föräldrar skilde sig.

77.

Seventy-seven is the 22nd discrete biprime and the first of the (7.q) family. Since both 7 and 11 are Gaussian primes, this means that 77 is a Blum integer.
77 has an aliquot sum of 19 and it is the second number to do so the first being 65; 77 is the 2nd member of the 19-aliquot tree.
It is the sum of three squares, 42 + 52 + 62, as well as the sum of the first eight prime numbers.
It also is the number of integer partitions of the number 12.
It is the largest number that cannot be written as a sum of distinct numbers whose reciprocals sum to 1.
77 and 78 form a Ruth–Aaron pair.
It is possible for a sudoku puzzle to have as many as 77 givens, yet lack a unique solution.
It and its sibling 49 are the only 2-digit numbers whose home primes (in base 10) have not been calculated.
It is the number of digits of the 12th perfect number.

Så 77. Ett inlägg om sig själv. Eller ett inlägg som bara är ett nummer.

Post #077 i #blogg100