Greatest k such that s(k) = n, where s = A026346.

Terms

a(0) =2a(1) =6a(2) =9a(3) =11a(4) =15a(5) =18a(6) =22a(7) =26a(8) =28a(9) =31a(10) =35a(11) =37a(12) =41a(13) =44a(14) =46a(15) =50a(16) =53a(17) =55a(18) =59a(19) =63a(20) =66a(21) =70a(22) =72a(23) =75a(24) =79a(25) =83a(26) =85a(27) =88a(28) =92a(29) =94