1,1

Question: For what values of n, k = n. i.e. 1,2,5,10, etc.

a(n) = n for n being: 7, 11, 13, 20, 21, 23, 25, 26, 29, 31, 37, 38, 39, 50, 52, 53, 58, 59, 62, 63, 65, 67, 71, 74, 81, 82, 85, 89, 91, 92, 95, 97, 100, 101, 106, 115, 116, 118, 130, 133, 145, 146, 152, 159, 169, 173, 175, 178, 182, 184, 185, 195, 196, 200, 212, 213, 214, 215, 217, 220, 221, 224, 227, 229, 230, 232, 235, 236, 239, 243, 250.

a(7) = 7 the corresponding k = 0, a(2) =210, k=2. a(4) = 432, k = 2.

f[n_] := Block[{j = n, k = n - 1}, While[j = ToExpression[ StringJoin[ ToString[j], ToString[k]]]; !IntegerQ[j/n] && k > -1, k-- ]; If[k == -1, Return[n], Return[j]]]; Table[f[n], {n, 1, 30}]

Cf. A069860, A069861, A069862.

Adjacent sequences: A069860 A069861 A069862 this_sequence A069864 A069865 A069866

Sequence in context: A027014 A088746 A112364 this_sequence A067642 A052245 A052246

base,nonn,uned

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 18 2002

Edited by Robert G. Wilson v (rgwv(AT)rgwv.com), Apr 22 2002