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A331523
a(n) is the least positive k such that A100271(n) - k^3 is a fourth power.
2
1, 1, 3, 2, 1, 3, 7, 8, 7, 1, 13, 6, 15, 15, 12, 16, 16, 2, 10, 20, 18, 21, 7, 16, 9, 22, 13, 22, 23, 24, 20, 10, 25, 12, 25, 22, 26, 27, 11, 26, 28, 30, 27, 31, 22, 31, 34, 30, 35, 36, 28, 31, 37, 8, 37, 16, 27, 36, 35, 40, 1, 3, 13, 31, 37, 28, 33, 42, 21
OFFSET
1,3
LINKS
EXAMPLE
The first terms, alongside A100271(n), are:
n a(n) A100271(n)
-- ---- ----------------
1 1 2 = 1^3 + 1^4
2 1 17 = 1^3 + 2^4
3 3 43 = 3^3 + 2^4
4 2 89 = 2^3 + 3^4
5 1 257 = 1^3 + 4^4
6 3 283 = 3^3 + 4^4
7 7 359 = 7^3 + 2^4
8 8 593 = 8^3 + 3^4
9 7 599 = 7^3 + 4^4
10 1 1297 = 1^3 + 6^4
PROG
(PARI) See Links section.
CROSSREFS
See A331435 for similar sequences.
Sequence in context: A078268 A124782 A106611 * A025261 A111572 A046900
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Jan 19 2020
STATUS
approved