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A217435 Number of prime factors of n^n+(n-1)^(n-1), counted with multiplicity. 5
1, 1, 1, 1, 4, 2, 3, 2, 3, 2, 5, 2, 6, 4, 2, 3, 6, 3, 3, 4, 6, 2, 7, 3, 5, 5, 3, 3, 5, 3, 3, 3, 7, 4, 5, 4, 3, 2, 2, 2, 6, 3, 6, 4, 5, 3, 8, 6, 6, 3, 5, 5, 5, 5, 3, 3, 5, 2, 8, 4, 4, 6, 6, 6, 8, 8, 4, 3, 4, 7, 7, 6, 6, 4, 4, 7, 9, 6, 7, 5, 9, 5, 7, 4, 3, 5, 6, 7, 9, 3, 2, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

M. F. Hasler, Table of n, a(n) for n = 1..112

W. Nissen, np ( n ) = n^n + (n+1)^(n+1) — 2 prominent questions, Oct 02 2012

W. Nissen, Prime factors of np ( n ) = n^n + (n+1)^(n+1), Up for the Count.

FORMULA

a(n) = A001222(A056788(n)).

MAPLE

A217435:=n->numtheory[bigomega](n^n+(n-1)^(n-1)): seq(A217435(n), n=1..30); # Wesley Ivan Hurt, Jan 27 2017

PROG

(PARI) for(n=1, 999, print1(bigomega((n-1)^(n-1)+n^n)", "))

CROSSREFS

Sequence in context: A068152 A278970 A182199 * A238352 A291357 A079636

Adjacent sequences:  A217432 A217433 A217434 * A217436 A217437 A217438

KEYWORD

nonn,hard

AUTHOR

M. F. Hasler, Oct 02 2012

EXTENSIONS

Data beyond a(49) from W. Nissen's web site.

STATUS

approved

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Last modified October 19 03:08 EDT 2019. Contains 328211 sequences. (Running on oeis4.)