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A063484 Omega(n+1) = 2*Omega(n), where Omega(n) is the number of prime divisors of n (with repetition). 1
3, 5, 13, 15, 35, 37, 39, 55, 61, 63, 73, 87, 134, 155, 157, 183, 193, 203, 209, 219, 247, 249, 259, 277, 295, 305, 313, 314, 327, 329, 339, 341, 371, 397, 399, 413, 421, 457, 458, 471, 489, 515, 535, 539, 541, 545, 579, 583, 613, 635, 649, 661, 673, 685, 689 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,1000

EXAMPLE

Omega(949)=2, Omega(949+1)=2*2, so 949 is a member of the sequence.

PROG

(PARI) j=[]; for(n=1, 1000, if(bigomega(n+1)==2*bigomega(n), j=concat(j, n))); j

(PARI) { n=0; for (m=1, 10^9, if (bigomega(m + 1) == 2*bigomega(m), write("b063484.txt", n++, " ", m); if (n==1000, break)) ) } \\ Harry J. Smith, Aug 23 2009

CROSSREFS

Sequence in context: A086769 A018753 A073217 * A057920 A018329 A090545

Adjacent sequences:  A063481 A063482 A063483 * A063485 A063486 A063487

KEYWORD

nonn

AUTHOR

Jason Earls, Jul 28 2001

STATUS

approved

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Last modified December 7 22:50 EST 2021. Contains 349590 sequences. (Running on oeis4.)