A034593 Cycle of 3 steps possible for 'concatenate a(n) and nextprime(a(n)) is a prime'.
467, 941, 8834, 9548, 13012, 22302, 23592, 26208, 47538, 58578, 78910, 86447, 86925, 116230, 118040, 123716, 128055, 213493, 234146, 238326, 273057, 285315, 286422, 389336, 399261, 457810, 468764, 481476, 502590, 525402, 541102, 570205
Offset: 0
Examples
a(n)=78910 -> nextprime(a(n)) is 78919 so '7891078919' is prime (=step 1); a(n2)=7891078919 -> nextprime(a(n2)) is 7891078931 so '78910789197891078931' is prime (=step 2); a(n3)=78910789197891078931 -> nextprime(a(n3)) is 78910789197891078949 so '7891078919789107893178910789197891078949' is prime (=step 3).