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A095172 Image of 1,1,1,... under the map Q. +0
3
1, 2, 3, 5, 6, 8, 11, 13, 17, 21, 24, 30, 34, 39, 47, 52, 60, 69, 76, 87, 97, 107, 121, 132, 147, 163, 177, 196, 213, 231, 254, 274, 298, 324, 347, 378, 406, 435, 471, 504, 541, 583, 621, 665, 711, 756, 808, 860, 915, 973, 1032, 1093, 1160, 1228, 1300, 1376, 1454 (list; graph; listen)
OFFSET

1,2

COMMENT

Define a map Q from a sequence c(1),c(2),c(3),... to a sequence d(1),d(2),d(3),... as follows:

Let A(0,k) be the starting sequence c(1),c(2), ... For m >= 1, define

A(m,k) = A(m-1,k) + A(m-1,k-A(m-1,m)) for k > A(m-1,m);

A(m,k) = A(m-1,k) for k <= A(m-1,m).

For example:

A(0,k):_1,1,1,1,1,1,1,1,1,1,...

+_______0,1,1,1,1,1,1,1,1,1,...

=A(1,k):1,2,2,2,2,2,2,2,2,2,...

+_______0,0,1,2,2,2,2,2,2,2,...

=A(2,k):1,2,3,4,4,4,4,4,4,4,...

+_______0,0,0,1,2,3,4,4,4,4,...

=A(3,k):1,2,3,5,6,7,8,8,8,8,...

+_______0,0,0,0,0,1,2,3,5,6,...

=A(4,k):1,2,3,5,6,8,10,11,13,14,...

+_______0,0,0,0,0,0,1,_2,_3,_5,...

=A(5,k):1,2,3,5,6,8,11,13,16,19,...

+_______0,0,0,0,0,0,0,_0,_1,_2,...

=A(6,k):1,2,3,5,6,8,11,13,17,21,...

(The numbers of leading 0's in the sequence following each + forms the limit-sequence.)

The limit sequence d(1),d(2),d(3),... shares its first 10 terms with T(6,k), so the limit sequence {T(m,k)} as m -> oo) begins 1,2,3,5,6,8,11,13,17,21,...

Comment from Christian G. Bower (bowerc(AT)usa.net), Jun 12 2004:

If we take the sequence whose g.f. is:

(1+x)(1+x^2)(1+x^3)(1+x^5)(1+x^6)(1+x^8)(1+x^11)...(1+x^d(n))...

we get:

1 1 1 2 1 2 3 2 4 4 3 6 4 5 8 5 8 9 7...

Taking the partial sums we get:

1 2 3 5 6 8 11 13 17 21 24 30 34 39 47 52 60 69 76...

the original sequence. More generally, Q appears to take sequence c to a sequence d such that if we take the Weigh transform of the characteristic function of d and convolve it with sequence c, we get the sequence d.

PROGRAM

(PARI) {d=57; A=vector(d, j, 1); m=1; while(d>A[m], B=A; for(k=1, d, if(k>A[m], B[k]=A[k]+A[k-A[m]])); A=B; m++); for(j=1, d, print1(A[j], ", "))} - Klaus Brockhaus, Jun 21 2004

CROSSREFS

Cf. A095173, A095174.

Adjacent sequences: A095169 A095170 A095171 this_sequence A095173 A095174 A095175

Sequence in context: A005099 A105760 A050834 this_sequence A127312 A081830 A117517

KEYWORD

nonn,nice,easy

AUTHOR

njas, based on correspondence from Leroy Quet (qq-quet(AT)mindspring.com), Jun 11 2004

EXTENSIONS

What happens if the map Q or its inverse is applied to other basic sequences such as powers of 2, Fibonacci numbers, triangular numbers, etc.?

More terms from Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Jun 21 2004

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Last modified October 13 20:18 EDT 2008. Contains 145016 sequences.


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