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A218448
First of a run of 5 consecutive numbers with same prime signature.
5
204323, 3252571, 5205074, 7201674, 20182921, 28387953, 36193650, 43216722, 51049537, 56155074, 57070850, 61961315, 62167075, 65425473, 76647074, 82507473, 92658049, 95943321, 100498849, 107236449, 109751473, 110899321, 112198075, 112477849, 116736323
OFFSET
1,1
COMMENTS
A number n is in this sequence iff n and n+1 is in A175590; also: iff n and n+2 are in A052214 (in which case n+1 is in A052214, too); and also: iff {n,n+1,n+2,n+3} are in A052213.
A034173(6) = A218448(62) = A218448(63)-1 is the least term n such that n+1 is also in the sequence.
LINKS
M. F. Hasler and Donovan Johnson, Table of n, a(n) for n = 1..1000 (first 140 terms from M. F. Hasler)
PROG
(PARI) is_A218448(n)={my(f); !for(i=0, 4, f!=(f=vecsort(factor(n+i)[, 2])) & i & return)}
(PARI) f(k)=vecsort(factor(k)[, 2]~, , 4)
t=f(n=2); while(n<1e8, for(i=n+1, n+4, tt=f(i); if(tt!=t, n=i; t=tt; next(2))); print1(n", "); n++) \\ Charles R Greathouse IV, Oct 28 2012
KEYWORD
nonn
AUTHOR
M. F. Hasler, Oct 28 2012
EXTENSIONS
a(6)-a(8) from Charles R Greathouse IV, Oct 28 2012
a(9)-a(25) from Donovan Johnson, Oct 28 2012
Values up to a(140) computed using b175590.txt from Charles R Greathouse IV - M. F. Hasler, Oct 28 2012
STATUS
approved