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A074256
Numbers k such that the sum of factorials of the digits of k equals the sum of the primes from the smallest prime factor of k to the largest prime factor of k.
0
2, 242, 1323, 3200, 13050, 30000, 42432, 132300, 426205, 442244, 620425, 665353, 1261645, 1306254, 1453032, 1461363, 1523340, 1523466, 2025012, 2105334, 2134350, 2205102, 2613504, 2713421, 3005264, 3312400, 3314520, 3432000
OFFSET
1,1
COMMENTS
Numbers k such that A061602(k) = A074036(k). - Andrew Howroyd, Sep 18 2024
EXAMPLE
242 = 2*11^2 and 2+3+5+7+11 = 28 and 2!+4!+2! = 28.
MATHEMATICA
okQ[n_]:=Module[{ifn=Transpose[FactorInteger[n]][[1]]}, Total[Prime[ Range[ PrimePi[ Min[ifn]], PrimePi[Max[ifn]]]]]==Total[IntegerDigits[n]!]]; Select[Range[ 2, 3500000], okQ] (* Harvey P. Dale, Apr 21 2011 *)
PROG
(PARI) isok(n)={my(d=digits(n), s=sum(k=1, #d, d[k]!), f=factor(n)[, 1]); if(#f, forprime(p=f[1], f[#f], s-=p)); s==0} \\ Andrew Howroyd, Sep 18 2024
CROSSREFS
Sequence in context: A294319 A055968 A068838 * A146312 A109930 A309037
KEYWORD
nonn,base
AUTHOR
Jason Earls, Sep 20 2002
EXTENSIONS
More terms from Michel ten Voorde, Jun 20 2003
More terms from Sam Alexander, Feb 28 2005
Offset changed by Andrew Howroyd, Sep 18 2024
STATUS
approved