A336189 The perfect square integer sum of a square block of integers, with 1 at the top-left corner, on a diagonally numbered 2D board.

1, 48841, 151757761, 7148452448281, 22211509021338121, 1046258952151234702321, 3250912043200499426917081, 153132136343696050161247674961, 475808694603918281112156880430641

Offset

1,2

Comments

See A336186 for the corresponding square edge length and an explanation of the sequence. Note that the currently known terms all end in 1.

Links

Table of n, a(n) for n=1..9.

Eric Angelini, Prime squares and square squares, personal blog "Cinquante signes", Jun. 29, 2020.

Eric Angelini, Prime squares and square squares, personal blog "Cinquante signes", Jun. 29, 2020. [Cached copy]

Example

a(1) = 1 = 1^2.
a(2) = 48841 = 221^2.
a(3) = 151757761 = 12319^2.
a(4) = 7148452448281 = 2673659^2.
a(5) = 22211509021338121 = 149035261^2.
a(6) = 1046258952151234702321 = 32345926361^2.
a(7) = 3250912043200499426917081 = 1803028575259^2.
a(8) = 153132136343696050161247674961 = 391321014441719^2.
a(9) = 475808694603918281112156880430641 = 21813039554448121^2.
See A336186 for a diagram of the 2D board and examples.

Crossrefs

Cf. A336186, A185505, A000290, A000124, A000217.

Sequence in context: A210401 A067869 A175278 * A157667 A176373 A237087

Adjacent sequences: A336186 A336187 A336188 * A336190 A336191 A336192

Keyword

nonn,more

Author

Scott R. Shannon and Eric Angelini, Jul 11 2020

Status

approved