A344709 - OEIS

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A344709

Terms of A343376 that are divisible by their indices.

1, 5, 20, 2068, 46624, 1504, 86903, 179869, 6326031, 2067552915248, 2115635541184, 261492434034413120, 423428386545586403520, 2142421239387370011840, 4330751505333040809648, 14503076032736674286321954837282691230684634768

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OFFSET

1,2

COMMENTS

For n >= 2, a(n) will be the last number in a run of strictly increasing terms of length A344712(n-1) in A343376. The first number in this run will be A343457(n-1).

LINKS

Table of n, a(n) for n=1..16.

FORMULA

a(n) = A343376(A343456(n)) for n >= 1.

EXAMPLE

k: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, ...

A343376(k): 0, 1, 1, 2, 3, 5, 1, 6, 7, 13, 20, 2, 22, 24, ...

x, D, x, x, x, D, x, x, x, x, D, x, x, x, ...

So, a(1) = 1, a(2) = 5, a(3) = 20, ...

MAPLE

A343376 := proc(n) local q; option remember; `if`(n < 2, n, `if`(irem(A343376(n - 1), n - 1, 'q') = 0, q, A343376(n - 1) + A343376(n - 2))); end proc;

q := n -> is(A343376(n + 1) = A343376(n)/n);

map(x -> A343376(x), select(q, [$ (1 .. 300)]))[];

CROSSREFS

Cf. A343376, A343456, A343457, A344712.

Sequence in context: A002030 A213148 A202860 * A156148 A224867 A156824

Adjacent sequences: A344706 A344707 A344708 * A344710 A344711 A344712

KEYWORD

nonn

AUTHOR

Timothy L. Tiffin, May 26 2021

STATUS

approved