A117331 Lexicographically earliest permutation of prime powers such that the exponents of succeeding terms increase at most by 1.

1, 2, 3, 4, 5, 7, 9, 8, 11, 13, 17, 19, 23, 25, 27, 16, 29, 31, 37, 41, 43, 47, 49, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 121, 125, 81, 32, 64, 127, 131, 137, 139, 149, 151, 157, 163, 167, 169, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227

Offset: 1

Author

Reinhard Zumkeller, Mar 08 2006

Keywords

• nonn

Comments

A025474(A095874(a(n+1))) - A025474(A095874(a(n))) <= 1;

A117332(n) = A095874(a(n));

a(A117333(n)) = A000961(n).

Examples

			a(13)..a(16): 23,5^2,3^3,2^4;
a(38)..a(43): 113,11^2,5^3,3^4,2^5,2^6;
a(239)..a(248): 1367,37^2,11^3,5^4,3^5,3^6,2^7,2^8,2^9,2^10.
		

Links

• Eric Weisstein's World of Mathematics, Prime Power