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A303216 A(n,k) is the n-th Fibonacci number with exactly k prime factors (counted with multiplicity); square array A(n,k), n>=1, k>=1, read by antidiagonals. 6
2, 21, 3, 8, 34, 5, 6765, 610, 55, 13, 2584, 196418, 987, 377, 89, 144, 701408733, 317811, 10946, 4181, 233, 832040, 102334155, 1134903170, 2178309, 75025, 17711, 1597, 86267571272, 267914296, 12586269025, 365435296162, 32951280099, 3524578, 121393, 28657 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Alois P. Heinz, Antidiagonals n = 1..16, flattened

FORMULA

A(n,k) = A000045(A303215(n,k)).

A001222(A(n,k)) = k.

EXAMPLE

Square array A(n,k) begins:

    2,    21,       8,         6765,           2584,                 144, ...

    3,    34,     610,       196418,      701408733,           102334155, ...

    5,    55,     987,       317811,     1134903170,         12586269025, ...

   13,   377,   10946,      2178309,   365435296162,      10610209857723, ...

   89,  4181,   75025,  32951280099,  6557470319842,    2111485077978050, ...

  233, 17711, 3524578, 139583862445, 72723460248141, 7540113804746346429, ...

MAPLE

F:= combinat[fibonacci]: with(numtheory):

A:= proc() local h, p, q; p, q:= proc() [] end, 2;

      proc(n, k)

        while nops(p(k))<n do q:= q+1;

          h:= bigomega(F(q));

          p(h):= [p(h)[], F(q)]

        od; p(k)[n]

      end

    end():

seq(seq(A(n, 1+d-n), n=1..d), d=1..10);

CROSSREFS

Columns k=1-2 give: A005478, A053409.

Row n=1 gives A072397.

Cf. A000045, A001222, A303215, A303218.

Sequence in context: A060600 A249646 A143247 * A303218 A162536 A100980

Adjacent sequences:  A303213 A303214 A303215 * A303217 A303218 A303219

KEYWORD

nonn,tabl

AUTHOR

Alois P. Heinz, Apr 19 2018

STATUS

approved

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Last modified November 20 12:13 EST 2019. Contains 329335 sequences. (Running on oeis4.)