A100039 - OEIS

A100039

Positions of occurrences of the natural numbers as fourth subsequence in A100035.

22, 35, 52, 73, 98, 127, 160, 197, 238, 283, 332, 385, 442, 503, 568, 637, 710, 787, 868, 953, 1042, 1135, 1232, 1333, 1438, 1547, 1660, 1777, 1898, 2023, 2152, 2285, 2422, 2563, 2708, 2857, 3010, 3167, 3328, 3493, 3662, 3835, 4012, 4193, 4378, 4567, 4760

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OFFSET

1,1

COMMENTS

n>1: A100035(a(n))=n and A100035(m)<>n for a(n-1)<=m<a(n);

A100036(n) < A100037(n) < A100038(n) < a(n).

LINKS

Table of n, a(n) for n=1..47.

FORMULA

2n^2 + 7n + 13 (conjectured). - Ralf Stephan, May 15 2007

EXAMPLE

First terms (10=A,11=B,12=C) of A100035(a(n)):

.....................1............2................3....

1231435425165764736271879869584938291A9BA8B7A6B5A4B3A2B1;

a(1) = A084849(4) = 22, A100035(22) = 1;

a(2) = A014107(4) = 35, A100035(35) = 2;

a(3) = A033537(5) = 52, A100035(52) = 3;

a(4) = A100040(6) = 73, A100035(73) = 4;

a(5) = A100041(7) = 98, A100035(98) = 5.

CROSSREFS

Sequence in context: A254691 A159518 A245365 * A061561 A233404 A167277

Adjacent sequences: A100036 A100037 A100038 * A100040 A100041 A100042

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Oct 31 2004

STATUS

approved