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.

User: Christopher Roat

Christopher Roat's wiki page.

Christopher Roat has authored 1 sequences.

A362343 Sequence that alternately doubles and squares the previous number; a(0) = 1.

Original entry on oeis.org

1, 2, 4, 8, 64, 128, 16384, 32768, 1073741824, 2147483648, 4611686018427387904, 9223372036854775808, 85070591730234615865843651857942052864, 170141183460469231731687303715884105728, 28948022309329048855892746252171976963317496166410141009864396001978282409984
Offset: 0

Author

Christopher Roat, Apr 17 2023

Keywords

Crossrefs

Cf. A075427.
Subsequence of A000079.

Programs

  • Python
    def A362343(n): return 1<<((1<<(n>>1)+1)-1 if n&1 else (1<<(n>>1)+1)-2) # Chai Wah Wu, Apr 23 2023

Formula

a(0) = 1; a(n) = a(n-1)*2 if n is odd, otherwise a(n) = a(n-1)^2.
a(n) = 2^A075427(n-1), for n>=1.