k times k+6 gives the concatenation of two numbers m and m+7.

Terms

a(0) =378a(1) =617a(2) =708a(3) =903a(4) =8761a(5) =45456a(6) =54539a(7) =693063a(8) =8181812a(9) =88235288a(10) =327935224a(11) =330669332a(12) =363636365a(13) =418318517a(14) =428571430a(15) =461538455a(16) =538461540a(17) =571428565a(18) =581681478a(19) =636363630a(20) =669330663a(21) =672064771a(22) =691571588