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A133255 Triangle with a minimum occurrence of prime powers for which the least common multiple of the rows will give the terms in A003418. 0
1, 1, 1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 4, 3, 1, 1, 1, 4, 3, 1, 5, 1, 1, 4, 3, 1, 5, 1, 1, 1, 4, 3, 1, 5, 1, 7, 1, 1, 8, 3, 1, 5, 1, 7, 1, 1, 1, 8, 9, 1, 5, 1, 7, 1, 1, 1, 1, 8, 9, 1, 5, 1, 7, 1, 1, 1, 1, 1, 8, 9, 1, 5, 1, 7, 1, 1, 1, 11, 1, 1, 8, 9, 1, 5, 1, 7, 1, 1, 1, 11, 1, 1, 1, 8, 9, 1, 5, 1, 7, 1, 1, 1, 11, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,6

COMMENTS

Checked up to 29:th row. Similar to A133232 and A133233. In this table the prime powers with the same base are in the same column. A prime power occurs in the table: (base of prime power-1)*(the prime power).

FORMULA

T(n,k) = if k=1 then 1 elseif n-1>=(A089026(n-1))^0 and n-1<(A089026(n-1))^1 then (A089026(n-1))^0 elseif n-1>=(A089026(n-1))^1 and n-1<(A089026(n-1))^2 then (A089026(n-1))^1 elseif n-1>=(A089026(n-1))^2 and n-1<(A089026(n-1))^3 then (A089026(n-1))^2 elseif n-1>=(A089026(n-1))^3 and n-1<(A089026(n-1))^4 then (A089026(n-1))^3 elseif n-1>=(A089026(n-1))^4 and n-1<(A089026(n-1))^5 then (A089026(n-1))^4 else 1 (1<=k<=n) And so on, this formula needs to be expanded if one wants to make a bigger table. A089026(n-1) means that the index to the that sequence is shifted in this formula so that the first term in A089026 is used in the second column of the table.

EXAMPLE

lcm{1}= 1

lcm{1,1} = 1

lcm{1,1,2} = 2

lcm{1,1,2,3} = 6

lcm{1,1,4,3,1} = 12

lcm{1,1,4,3,1,5} = 60

lcm{1,1,4,3,1,5,1} = 60

lcm{1,1,4,3,1,5,1,7} = 420

lcm{1,1,8,3,1,5,1,7,1} = 840

lcm{1,1,8,9,1,5,1,7,1,1} = 2520

1 = 1

1*1 = 1

1*1*2 = 2

1*1*2*3 = 6

1*1*4*3*1 = 12

1*1*4*3*1*5 = 60

1*1*4*3*1*5*1 = 60

1*1*4*3*1*5*1*7 = 420

1*1*8*3*1*5*1*7*1 = 840

1*1*8*9*1*5*1*7*1*1 = 2520

PROG

(Excel cell formula) =if(column()=1; 1; if(and(row()-1>=(A089026(n-1))^0; row()-1<(A089026(n-1))^1); (A089026(n-1))^0; if(and(row()-1>=(A089026(n-1))^1; row()-1<(A089026(n-1))^2); (A089026(n-1))^1; if(and(row()-1>=(A089026(n-1))^2; row()-1<(A089026(n-1))^3); (A089026(n-1))^2; if(and(row()-1>=(A089026(n-1))^3; row()-1<(A089026(n-1))^4); (A089026(n-1))^3; if(and(row()-1>=(A089026(n-1))^4; row()-1<(A089026(n-1))^5); (A089026(n-1))^4; 1)))))) And so on.

CROSSREFS

Cf. A089026, A003418, A000961.

Sequence in context: A202176 A168443 A156041 * A145972 A152650 A184219

Adjacent sequences:  A133252 A133253 A133254 * A133256 A133257 A133258

KEYWORD

nonn,tabl,uned

AUTHOR

Mats Granvik (mgranvik(AT)abo.fi), Oct 14 2007

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Last modified February 14 09:18 EST 2012. Contains 205614 sequences.