A209835 Smallest k >= 0 such that 2k + (n-th average of twin prime pairs) is oblong number.

1, 0, 0, 1, 0, 0, 6, 0, 4, 1, 9, 3, 1, 9, 6, 6, 0, 1, 12, 15, 16, 0, 15, 0, 15, 15, 0, 16, 4, 21, 1, 24, 21, 6, 24, 18, 12, 3, 30, 15, 19, 15, 27, 21, 15, 6, 27, 15, 0, 36, 16, 10, 27, 12, 0, 9, 10, 7, 24, 15, 36, 21, 40, 37, 25, 16, 10, 9, 42, 21, 6, 34, 0, 30, 49, 34, 22, 13, 36, 30, 0

Offset

1,7

Comments

Averages of twin prime pairs of the form n(n+1): 6, 12, 30, 42, 72, 240, 420, 462, 600, 1482, 1722, 2550, 2970, 3540, 4422, 8010, 10302, 17292, 19182, 20022, 23562, 24180, 27060, 31152... , multiples of 6 as stated in A002822.

Links

Table of n, a(n) for n=1..81.

Crossrefs

Cf. A002378, A014574.

Sequence in context: A019766 A094830 A196878 * A344973 A298528 A341325

Adjacent sequences: A209832 A209833 A209834 * A209836 A209837 A209838

Keyword

nonn

Author

Gerasimov Sergey, Mar 14 2012

Extensions

Corrected by R. J. Mathar, Mar 15 2012

Status

approved