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Search: id:A129341
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| A129341 |
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Numbers n such that n-th and (n+1)th triangular numbers have no common digit. |
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+0
1
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| 0, 1, 2, 3, 7, 8, 10, 11, 12, 23, 27, 31, 34, 36, 41, 76, 88, 631, 774, 893, 2827
(list; graph; listen)
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OFFSET
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1,3
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COMMENT
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No more terms <5000000. Is the sequence finite?
The PARI program shows that there is no further term up to 10^100. - Robert Gerbicz (robert.gerbicz(AT)gmail.com), Jun 10 2007
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EXAMPLE
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n=893: T(n)=399171, T(n+1)=400065; n=2827: T(n)=3997378, T(n+1)=4000206.
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PROGRAM
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(PARI) M=-1; for(h=0, 200, for(k=1, 9, b=(sqrtint(8*k*10^h)-1)\2; d1=d2=vector(10, n, 0); n=b*(b+1)/2; while(n>0, d1[n%10+1]=1; n\=10); n=(b+1)*(b+2)/2; while(n>0, d2[n%10+1]=1; n\=10); T=1; for(i=1, 10, if(d1[i]*d2[i]>0, T=0; break)); if(T&&(M<b), M=b; print1(b, ", ")))) - Robert Gerbicz (robert.gerbicz(AT)gmail.com), Jun 10 2007
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CROSSREFS
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Cf. A000217.
Sequence in context: A123644 A105266 A054996 this_sequence A115985 A131210 A088340
Adjacent sequences: A129338 A129339 A129340 this_sequence A129342 A129343 A129344
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KEYWORD
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base,nonn
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AUTHOR
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Zak Seidov (zakseidov(AT)yahoo.com), May 28 2007
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