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A108065 Numbers n such that DENEAT(n!) is prime, where DENEAT(n) = concatenate number of even digits in n, number of odd digits and total number of digits. 1
1, 2, 3, 10, 15, 29, 35, 39, 51, 65, 167, 185, 198, 250, 282, 325, 366, 368, 382, 396, 400, 403, 450, 453, 509, 574, 575, 590, 598, 601, 699, 720, 759, 764, 788, 791, 797, 817, 824, 860, 863, 865, 867, 877, 901, 909, 911, 913, 930, 936, 1066, 1068, 1081, 1145 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

10 is in the sequence because 10! = 3628800 has 6 even digits, 1

odd digit and 7 total digits, yielding the prime 617.

MATHEMATICA

eotQ[n_]:=Module[{idnf=IntegerDigits[n!], len, ev, od}, len=Length[idnf]; ev= Count[ idnf, _?EvenQ]; od=Count[idnf, _?OddQ]; PrimeQ[FromDigits[ Flatten[ IntegerDigits/@ Join[{ev, od, len}]]]]]; Select[Range[1200], eotQ] (* Harvey P. Dale, Jul 05 2017 *)

CROSSREFS

Cf. A073053.

Sequence in context: A194544 A075770 A135101 * A187767 A226881 A026336

Adjacent sequences:  A108062 A108063 A108064 * A108066 A108067 A108068

KEYWORD

base,nonn

AUTHOR

Jason Earls, Jun 03 2005

STATUS

approved

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Last modified October 19 16:17 EDT 2019. Contains 328223 sequences. (Running on oeis4.)