A308058 - OEIS

A308058

Lexicographically earliest sequence of positive terms such that for any distinct m and n, a(m) * a(m+1)^2 <> a(n) * a(n+1)^2.

1, 1, 2, 1, 3, 1, 4, 3, 2, 2, 3, 3, 4, 4, 5, 1, 5, 2, 4, 6, 1, 7, 1, 9, 5, 3, 5, 4, 7, 2, 5, 5, 6, 2, 6, 3, 6, 4, 8, 4, 9, 7, 3, 7, 4, 10, 1, 11, 1, 13, 1, 17, 1, 19, 1, 22, 1, 23, 1, 24, 3, 8, 5, 7, 5, 8, 6, 5, 9, 9, 10, 2, 7, 6, 7, 7, 8, 7, 9, 11, 2, 9, 12

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OFFSET

1,3

COMMENTS

This sequence has similarities with A088178; here we consider a(n)*a(n+1)^2, there we consider a(n)*a(n+1).

LINKS

Rémy Sigrist, Table of n, a(n) for n = 1..10000

EXAMPLE

The first terms, alongside a(n)*a(n+1)^2, are:

n a(n) a(n)*a(n+1)^2

-- ---- -------------

1 1 1

2 1 4

3 2 2

4 1 9

5 3 3

6 1 16

7 4 36

8 3 12

9 2 8

10 2 18

PROG

(PARI) s=0; v=1; for(n=1, 83, print1(v", "); for (w=1, oo, if (!bittest(s, x=v*w^2), s+=2^x; v=w; break)))

CROSSREFS

See A308057 for an additive variant.

Cf. A088178.

Sequence in context: A020653 A094522 A233204 * A118487 A241006 A249148

Adjacent sequences: A308055 A308056 A308057 * A308059 A308060 A308061

KEYWORD

nonn

AUTHOR

Rémy Sigrist, May 10 2019

STATUS

approved