login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A144253
Bases and exponents in the prime decomposition of n replaced by digits of the Gregorian Calendar with these indices.
1
1, 3, 6, 5, 256, 2, 18, 5, 256, 27, 30, 2, 12288, 6, 12, 59049, 729, 5, 524288, 3, 15552, 56, 18, 5, 2048, 729, 12, 387420489, 3645, 2, 0, 3, 7776, 16, 1, 18, 200, 2, 18, 12, 9, 3, 90, 2, 32, 3645, 16, 1, 750, 25, 8, 18, 324, 1, 5103
OFFSET
1,2
COMMENTS
Start from the prime decomposition of n, not writing down exponents which are 1. That is the list 0, 1, 2, 3, 2^2, 5, 2*3, 7, 2^3, 3^2, 2*5, 11, 2^3*3, 13, 2*7, 3*5, 2^4, 17, 2*3^2, ... Replace each number i in this representation by the i-th digit in the Gregorian Calendar: 1(365(28 Feb)), 2(365(28 Feb)), 3(365(28 Feb)), 4(366(29 Feb)), 5(365(28 Feb)), ... This generates the sequence, namely 1, 3, 6, 5, 2^8, 2, 3*6, 5, 2^8, 3^3, 6*5, 2, 8^4*3, 6, 6*2, 9^5, 3^6, 5, 2*8^6, ...
EXAMPLE
2*8^6 = 2560 = a(19).
3 = a(20).
6^5*2 = 93312 = a(21).
8*7 = 56 = a(22).
3*6 = 18 = a(23).
5 = a(24),
2^8*8 = 2048 = a(25),
etc.
CROSSREFS
Sequence in context: A300673 A335633 A009193 * A152422 A332133 A256460
KEYWORD
nonn,less,base
AUTHOR
STATUS
approved