A076641 Integers read backwards, but with repetitions omitted.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 21, 31, 41, 51, 61, 71, 81, 91, 12, 22, 32, 42, 52, 62, 72, 82, 92, 13, 23, 33, 43, 53, 63, 73, 83, 93, 14, 24, 34, 44, 54, 64, 74, 84, 94, 15, 25, 35, 45, 55, 65, 75, 85, 95, 16, 26, 36, 46, 56, 66, 76, 86, 96, 17, 27, 37, 47, 57, 67, 77, 87, 97

Offset: 0

Author

Francois Jooste (phukraut(AT)hotmail.com), Oct 23 2002

Keywords

• easy
• nonn
• base

Comments

Although this is a list, it seems most natural here to have offset 0. - N. J. A. Sloane, Dec 09 2020

Examples

			10 backwards is 01=1, but 1 already appears, so omit it.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 0..10000
• Dana G. Korssjoen, Biyao Li, Stefan Steinerberger, Raghavendra Tripathi, and Ruimin Zhang, Finding structure in sequences of real numbers via graph theory: a problem list, arXiv:2012.04625, Dec 08, 2020

Crossrefs

Cf. A004086.

Programs

Haskell

a076641 = a004086 . a067251  -- Reinhard Zumkeller, Aug 12 2013

Maple

s := (L::list)->sum(L[i]*10^(nops(L)-i),i=1..nops(L)); d := (X::posint)->convert(X,base,10); SD := K->[seq(s(d(k)),k=1..K)];

Extensions

a(0) = 0 added by N. J. A. Sloane, Dec 09 2020