A063777 - OEIS

A063777

t(n^2) is a square and sets a new record for such squares, where t(n) = (sigma(n)-n)*omega(n); or t(n)= A001065(n)*A001221(n).

1, 3, 49, 114, 290, 1266, 3026, 4587, 8642, 14949, 21504, 47976, 74535, 79922, 102818, 112960, 172658, 280226, 632018, 662546, 693794, 791858, 969698, 1516322, 1758962, 2128898, 2184626, 2298242, 2414738, 2594882, 2718578, 3106946, 3174194, 3450386, 3521234

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..35.

EXAMPLE

t(49^2) = 400, a square.

PROG

(PARI) a=0; t(n) = (sigma(n)-n)*omega(n);

for(n=1, 10^7, x=t(n^2); if(issquare(x), b=x; if(b>a, a=b; print1(n, ", "))))

(PARI) t(n) = (sigma(n) - n)*omega(n);

{ n=0; a=-1; for (m=1, 10^9, if(issquare(b=t(m^2)), if(b>a, a=b; write("b063777.txt", n++, " ", m); if (n==31, break))) ) } \\ Harry J. Smith, Aug 31 2009

CROSSREFS

Cf. A001065, A001221.

Sequence in context: A160763 A041523 A054206 * A359886 A212651 A225317

Adjacent sequences: A063774 A063775 A063776 * A063778 A063779 A063780

KEYWORD

nonn

AUTHOR

Jason Earls, Aug 16 2001

EXTENSIONS

More terms from Sean A. Irvine, May 13 2023

STATUS

approved