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A307785 a(n) is the cubic root of A175428(n) + A175428(n+1). 1
2, 3, 4, 5, 6, 7, 6, 3, 4, 5, 6, 7, 6, 3, 4, 5, 6, 7, 6, 3, 4, 5, 6, 7, 6, 3, 4, 5, 6, 7, 6, 3, 4, 5, 6, 7, 6, 3, 4, 5, 6, 7, 8, 7, 4, 5, 6, 5, 2, 3, 4, 5, 6, 7, 6, 2, 3, 4, 5, 6, 7, 8, 9, 8, 5, 4, 5, 6, 7, 8, 7, 5, 6, 7, 6, 4, 5, 6, 7, 8, 9, 10, 9, 6, 5, 6, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The sum of two consecutive terms of A175428 is always a perfect cube.

LINKS

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

FORMULA

a(n)^3 = A175428(n) + A175428(n+1).

EXAMPLE

for n = 6:

- A175428(6) + A175428(7) = 135 + 208 = 343 = 7^3,

- hence a(6) = 7.

PROG

(PARI) p=1; s=0; for (n=1, 87, s+=2^p; for (v=1, oo, if (!bittest(s, v) && ispower(p+v, 3, &q), print1 (q ", "); p=v; break)))

CROSSREFS

Cf. A175428.

Sequence in context: A038389 A058223 A245355 * A331305 A279313 A063265

Adjacent sequences:  A307782 A307783 A307784 * A307786 A307787 A307788

KEYWORD

nonn

AUTHOR

Rémy Sigrist, Apr 28 2019

STATUS

approved

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Last modified August 7 13:52 EDT 2022. Contains 355989 sequences. (Running on oeis4.)