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(35S) OEIS A137442: N^2 THEN SMALLEST NOT YET LISTED & SUM - Gerald H - 12-09-2014 02:59 PM
Sequence of square then smallest integer not yet listed starting at 1^2, OEIS A137442
1, 2, 4, 3, 9, 5, 16, 6, 25, 7, 36, 8, 49, 10, 64, 11, 81, 12, 100, 13, 121, 14, 144, 15, 169, 17, 196, 18, 225, 19, 256, 20, 289, 21, 324, 22, 361, 23, 400, 24, 441, 26, 484, 27, 529…..
For index N solve the equation
G = RMDR( N , 2 ) ► R * SQ( ( N + 1 ) / 2 ) + ( 1 – R ) * ( N / 2 + IP( SQRT( N / 2 ) + 0.5 ) ) + 0 * ( ( IDIV( N , 2 ) ► F + R ) ► T * ( 1 + T * ( 3 + 2 * T ) ) / 6 + ( F + IP( SQRT( F ) + 0.5 ) ► Q ) * ( Q + 1 ) / 2 – ( IP( SQRT( Q ) ) ► U ) * ( U + 1 ) * ( U + 0.5 ) / 3 ► S )
for G. You will be prompted for values other than N, ignore these prompts with R/S.
For input
N = 818
The calculator returns
G = 429
Additionally the sum (OEIS A167390) of the first 818 terms is stored in S,
S = 22,979,050