Useless informations
• My Erdös number is 3 • My first name is a Lyndon word: arnaud < aud < d < naud < rnaud < ud
• The Christoffel word of slope 19/3 is: abbbbbbabbbbbbabbbbbbb
• I am born a totally prime day: 19/3/1973 (19, 3, 73 and also 1973 are prime numbers)
• My day and month of birth are both included in my year of birth: 1973
• Remark that (19+3)/7≃π
• 3, 19 and 73 are the 3 smallest prime numbers of the form 2xn2+1: 3=2x12+1, 19=2x32+1 and 73=2x62+1 (OEIS:A090698)
• 1, 9, 7 and 3 form the four corners of a numeric keypad
• 1973 is prime and:
• the mean of its divisors is a Fibonacci number: (1973+1)/2=987 (OEIS:A272440)
• the mean of its digits is prime: (1+9+7+3)/4=5 (OEIS:A285226)
• 1973-19-3=1951 is also prime
• is the sum of 3 consecutive primes: 1973=653+659+661 (OEIS:A034962)
• is the concatenation of primes: 19.73, 197.3 or 19.7.3 (OEIS:A238057, OEIS:A080906)
• its conjugates are products of exactly two primes: 3197=23x139, 7319=13x563 and 9731=37x263
• is the minimal prime containing exactly 7 prime substrings: 3, 7, 19, 73, 97, 197, 1973 (OEIS:A213321)
• is the minimal prime containing at least one of each digits in {1, 3, 7, 9} (OEIS:A108386)
• is a prime Leonardo number (OEIS:A145912)
• Consider 1973 as a circular or (bi-)infinite string (...19731973197...):
• the sum of 3 consecutive digits is always prime: 1+9+7=17, 9+7+3=19, 7+3+1=11, 3+1+9=13 (OEIS:A086259)
• the absolute difference between 2 consecutive digits is always a power of 2: |1-9|=23, |9-7|=21, |7-3|=22, |3-1|=21
• Consider 19/3/1973 as GPS coordinates 19.3 degrees of north latitude and 19.73 degrees of east longitude then you'll be dropped in the middle of nowhere, in the desert of Chad