A163744 Smallest positive m such that A050410(m) = 0 (mod n!).

1, 1, 3, 4, 23, 23, 608, 3703, 59063, 65975, 65975, 65975, 3227648, 83180983

Offset

1,3

Comments

Smallest positive m such that m-th truncated square pyramid number tsp(m)=m*(7*m-1)*(2*m-1)/6 is divisible by n!, n=0,1,.. .

Links

Table of n, a(n) for n=1..14.

Example

a(3)=3 because tsp(3)=126 is divisible by 3!: 126/3!=21
a(5)=23 because tsp(23)=27600 is divisible by 5!: 27600/5!=230
a(6)=608 because tsp(608)=523875600 is divisible by 6!: 523875600/6!=727605.

Crossrefs

Cf. A050410 Truncated square pyramid numbers:a(n)=sum(k^2, k=n..2*n-1)=(1/6)n(7n-1)(2n-1).

Sequence in context: A167452 A316192 A122660 * A221643 A042595 A002351

Adjacent sequences: A163741 A163742 A163743 * A163745 A163746 A163747

Keyword

more,nonn

Author

Zak Seidov, Aug 03 2009

Status

approved