The Goldbach conjecture [La conjecture de Goldbach].
4 = 2+2 6 = 3+3 8 = 3+5 [= 5+3] 10 = 3+7 = 5+5 [= 7+3] (...) 990 = 7+983 = 13+977 = 19+971 = 23+967 = 37+953 = 43+947 = 53+937 = 61+929 = 71+919 = 79+911 = 83+907 = 103+887 = 107+883 = 109+881 = 113+877 = 127+863 = 131+859 = 137+853 = 151+839 = 163+827 = 167+823 = 179+811 = 181+809 = 193+797 = 229+761 = 233+757 = 239+751 = 251+739 = 257+733 = 263+727 = 271+719 = 281+709 = 307+683 = 313+677 = 317+673 = 331+659 = 337+653 = 347+643 = 349+641 = 359+631 = 373+617 = 383+607 = 389+601 = 397+593 = 419+571 = 421+569 = 433+557 = 443+547 = 449+541 = 467+523 = 487+503 = 491+499 [= 499+491 = 503+487 = 523+467 = 541+449 = 547+443 = 557+433 = 569+421 = 571+419 = 593+397 = 601+389 = 607+383 = 617+373 = 631+359 = 641+349 = 643+347 = 653+337 = 659+331 = 673+317 = 677+313 = 683+307 = 709+281 = 719+271 = 727+263 = 733+257 = 739+251 = 751+239 = 757+233 = 761+229 = 797+193 = 809+181 = 811+179 = 823+167 = 827+163 = 839+151 = 853+137 = 859+131 = 863+127 = 877+113 = 881+109 = 883+107 = 887+103 = 907+83 = 911+79 = 919+71 = 929+61 = 937+53 = 947+43 = 953+37 = 967+23 = 971+19 = 977+13 = 983+7] (...)Each straight line displays an even integer number N such that:
N = P1+P2the two prime numbers P1 and P2 being displayed using the {x=P1,y=P2} coordinates. In order to exhibit the commutativity of the addition, both {P1,P2} and {P2,P1} couples are displayed, hence the symmetry.