A076215 Square root of sum defined in A007475(n) and A001032(n).

1, 5, 77, 92, 70, 195, 143, 3854, 357, 245, 413, 4088, 2257, 2222, 652, 679, 278949, 3366, 1281, 67963, 1612, 8555, 1518, 63412, 1159158, 2619, 2725, 13862, 60973, 3069, 10790, 3128, 4620, 5083, 42918, 3406

Offset

1,2

Comments

6a(n)^2 is divisible by A001032(n). Proof: Let s = A007475(n), n = A001032(n), then a(n)^2 = sum(k=s, s+n-1, k^2) = n/6*(2n^2+(6s-3)n+6s^2-6s+1).

Links

Christopher E. Thompson, Table of n, a(n) for n = 1..10438

Example

A001032(3)=11, A007475(3)=18, so 18^2+19^2+...+28^2 (11 terms) = 77^2.

Crossrefs

Cf. A001032, A007475.

Sequence in context: A144997 A088756 A319186 * A202607 A222533 A059856

Adjacent sequences: A076212 A076213 A076214 * A076216 A076217 A076218

Keyword

nonn

Author

Ralf Stephan, Nov 03 2002

Extensions

Offset corrected to 1 (to match A001032) by M. F. Hasler, Feb 02 2016

Status

approved