cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A350779 Indices where Iccanobif numbers of the form A014258 decrease, i.e., numbers k such that A014258(k) < A014258(k-1).

Original entry on oeis.org

10, 17, 19, 20, 21, 23, 28, 31, 32, 39, 41, 45, 50, 55, 58, 60, 66, 70, 73, 75, 78, 83, 84, 90, 92, 95, 100, 101, 103, 105, 113, 114, 117, 123, 126, 129, 131, 140, 143, 147, 149, 151, 153, 155, 157, 163, 166, 167, 174, 176, 184, 197, 200, 206, 208, 210, 215, 217
Offset: 1

Views

Author

Chai Wah Wu, Jan 15 2022

Keywords

Examples

			A014258(17) = 715297 < 739401 = A014258(16), so 17 is a term.
		

Crossrefs

Cf. A014258.

Programs

  • Mathematica
    Flatten[Position[s,#]&/@Select[s=NestList[{Last@#,FromDigits@Reverse@IntegerDigits@Total@#}&,{0,1},220],!OrderedQ@#&]]  (* Giorgos Kalogeropoulos, Jan 16 2022 *)
  • Python
    from itertools import count, islice
    def A350079_gen(): # generator of terms
        a, b = 0, 1
        for n in count(1):
            if b < a:
                yield n
            a, b = b, int(str(a+b)[::-1])
    A350079_list = list(islice(A350079_gen(),20))