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A077655 Number of consecutive successors of n having the same number of prime factors as n (counted with multiplicity). 4
0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 2, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 1, 0, 0, 0, 0, 0, 0, 2, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,33

COMMENTS

If a(n) > 0 then a(n+1) = a(n)-1.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..100000

EXAMPLE

33=3*11 has only two successors also with two factors: 34=2*17 and 35=5*7 (whereas 33+3=36=2*2*3*3), therefore a(33)=2.

MATHEMATICA

snpf[n_]:=Module[{f=PrimeOmega[n], k=0}, While[f==PrimeOmega[n+k], k++]; k]; Array[snpf, 110]-1 (* Harvey P. Dale, Aug 01 2021 *)

PROG

(PARI) A077655(n) = { my(k=n+1, w=bigomega(n)); while(bigomega(k)==w, k++); (k-n)-1; }; \\ Antti Karttunen, Jan 22 2020

CROSSREFS

Cf. A001222, A077656, A045920, A045939, A045940, A045941, A045942, A077657.

Sequence in context: A037874 A343870 A339070 * A117886 A145723 A085977

Adjacent sequences:  A077652 A077653 A077654 * A077656 A077657 A077658

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Nov 13 2002

STATUS

approved

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Last modified December 3 18:19 EST 2021. Contains 349467 sequences. (Running on oeis4.)