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Search: id:A067779
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| A067779 |
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Primes such that the sum of the squares of its digits is equal to the product of its digits. |
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+0
1
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| 11353, 13513, 15313, 15331, 31153, 31513, 31531, 33151, 35311, 51133, 53113, 1125221, 1212251, 1212521, 1221251, 1252211, 1512221, 2115221, 2122151, 2122511, 2151221, 2152211, 2215211, 2221511, 2251121, 2251211, 5122121
(list; graph; listen)
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OFFSET
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0,1
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EXAMPLE
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An eight-digit term is 11224121, a ten-digit term is 1111111843.
11353 belongs to the sequence because 1^2+1^2+3^2+5^2+3^2=45=1*1*3*5*3
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PROGRAM
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(PARI) for(k=1, 370000, p=prime(k); n=p; sd=0; pd=1; while(n>0, d=divrem(n, 10); n=d[1]; sd=sd+d[2]*d[2]; pd=pd*d[2]); if(sd==pd, print1(p, ", ")))
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CROSSREFS
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Adjacent sequences: A067776 A067777 A067778 this_sequence A067780 A067781 A067782
Sequence in context: A104017 A072959 A067791 this_sequence A082440 A083975 A115753
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KEYWORD
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easy,nonn
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AUTHOR
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Felice Russo (felice.russo(AT)katamail.com), Feb 06 2002
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EXTENSIONS
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Edited and extended by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de) Feb 11 2002
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