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Ormiston pairs
Two consecutive primes whose digits are equal, order apart, form an Ormiston pair.

The first two such pair are (1913, 1931) and (18379, 18397), while the first triplet, quadruple and quintuple are (11117123, 11117213, 11117321), 6607882000+(123,213,231,321) and 20847942560000+(0791,0917,0971,1097).

J.K.Andersen has determined that the smallest triple using only two distinct digits is 1311111133113111000 + (133, 313, 331). Among other results, he also found a 74-digit 9-tuple.

Every number greater than 119639 can be written as the sum of Ormiston numbers.

The first Ormiston pairs are (1913, 1931), (18379, 18397), (19013, 19031), (25013, 25031), (34613, 34631), (35617, 35671), (35879, 35897), (36979, 36997), (37379, 37397), (37813, 37831), (40013, 40031) more terms

Ormiston pairs can also be... (you may click on names or numbers and on + to get more values)

a-pointer 114031 163697 + 1998447697 1998757273 1999206271 aban 1000213 1000231 + 1992000631 1995000313 1995000331 alternating 250109 276781 + 989616109 989694569 989696341 amenable 1913 18397 + 999996113 999997697 999999113 apocalyptic 18379 18397 + 19031 25013 25031 arithmetic 1913 1931 + 9990797 9994613 9994631 balanced p. 34631 66431 + 1999772179 1999838531 1999965379 bemirp 1969081091 c.decagonal 4072531 6991531 + 1960695031 1981542781 1999100101 c.heptagonal 18397 114031 + 1384294297 1397271331 1841290613 c.pentagonal 139831 2644531 + 1779089131 1815554131 1939265131 c.square 19013 37813 + 1929136613 1976632813 1986075313 c.triangular 623071 6744781 + 1523401939 1871624479 1966148731 Chen 1913 1931 + 99992831 99996779 99999131 congruent 18397 19013 + 9990797 9994613 9994631 Cunningham 215297 820837 + 1915287697 1950458897 1980784037 Curzon 85313 93113 + 199912913 199964573 199977773 cyclic 1913 1931 + 9990797 9994613 9994631 d-powerful 135497 235997 + 9825731 9841397 9965479 de Polignac 34631 35897 + 99988331 99996779 99999113 deficient 1913 1931 + 9990797 9994613 9994631 dig.balanced 18397 34613 + 199919897 199922497 199972873 economical 1913 1931 + 19989971 19996279 19996297 emirp 1913 18379 + 199977779 199977797 199994279 equidigital 1913 1931 + 19989971 19996279 19996297 evil 1913 18397 + 999997679 999999113 999999131 Friedman 250091 559813 773879 good prime 40693 94397 + 198298871 199678769 199882217 happy 56179 56197 + 9941573 9947437 9947473 hex 2784997 2967091 + 1879277437 1880478997 1979851231 Hogben 37831 530713 + 1898301331 1915769131 1997598331 Honaker 1913 35617 + 998511109 998779031 999003913 iban 240473 343373 447173 inconsummate 1931 25031 + 936731 943913 969131 junction 19031 25013 + 99882137 99916337 99940639 lucky 18397 36997 + 9936679 9947473 9953071 m-pointer 116113 611113 + 111131213 111611113 1161111113 modest 1000231 1900813 + 1964037037 1975015873 1990004329 nialpdrome 55331 66431 + 997555331 998555531 999666431 odious 1931 18379 + 999986297 999996131 999997697 palindromic 1303031 1333331 + 977252779 977606779 977999779 palprime 1303031 1333331 + 977252779 977606779 977999779 pancake 66431 109279 + 1911567197 1971135079 1978676779 pernicious 1931 35879 + 9988313 9990779 9990797 plaindrome 122579 123379 + 1444455679 1455566779 1566677779 prime 1913 1931 + 1999995731 1999996879 1999996897 primeval 1012379 Proth 464897 925697 + 1807876097 1823014913 1938358273 repunit 37831 530713 + 1898301331 1915769131 1997598331 self 40213 48109 + 999962479 999980231 999992537 self-describing 18103331 1422331931 1733221531 1822143331 1910223331 star 379513 465373 + 1960992973 1970550037 1992575713 strobogrammatic 1619696191 strong prime 1931 18397 + 99992831 99996797 99997897 super-d 1931 19013 + 9987031 9988331 9994631 truncatable prime 36997 37397 + 973564937 993946997 1543279337 twin 1931 25031 + 999958931 999962479 999980897 uban 37000079 37000097 + 1008000031 1063000079 1063000097 Ulam 19031 34613 + 9944531 9953107 9961613 upside-down 13146979 13282879 + 1399911179 1763467439 1978462319 weak prime 1913 18379 + 99997879 99999113 99999131 weakly prime 2474431 29348797 + 1985370731 1985538197 1993416713